Brand names: Astramorph/PF, Avinza, DepoDur, Duramorph, Infumorph, ... show all 9 brands Kadian, MS Contin, Oramorph SR, RMS
Drug class: Opiate Agonists
VA class: CN101
CAS number: 6211-15-0

Medically reviewed by Drugs.com on Apr 19, 2023. Written by ASHP.

Introduction

Opiate agonist; phenanthrene derivative.

Uses for Morphine

Pain (Acute or Chronic)

Strong analgesic used in the relief of severe, acute pain or moderate to severe, chronic pain (e.g., in terminally ill patients).

Extended-release preparations are used orally for management of moderate to severe pain when a continuous, around-the-clock analgesic is needed for an extended period of time. Extended-release preparations are not indicated for relief of acute pain or for use on an as-needed (“prn”) basis.

In symptomatic treatment of acute pain, reserve opiate analgesics for pain resulting from severe injuries, severe medical conditions, or surgical procedures, or when nonopiate alternatives for relieving pain and restoring function are expected to be ineffective or are contraindicated. Use smallest effective dosage for shortest possible duration since long-term opiate use often begins with treatment of acute pain. Optimize concomitant use of other appropriate therapies. (See Managing Opiate Therapy for Acute Pain under Dosage and Administration.)

Generally use opiates for management of chronic pain (i.e., pain lasting >3 months or past the time of normal tissue healing ) that is not associated with active cancer treatment, palliative care, or end-of-life care only if other appropriate nonpharmacologic and nonopiate pharmacologic strategies have been ineffective and expected benefits for both pain relief and functional improvement are anticipated to outweigh risks.

If used for chronic pain, opiate analgesics should be part of an integrated approach that also includes appropriate nonpharmacologic modalities (e.g., cognitive-behavioral therapy, relaxation techniques, biofeedback, functional restoration, exercise therapy, certain interventional procedures) and other appropriate pharmacologic therapies (e.g., nonopiate analgesics, analgesic adjuncts such as selected anticonvulsants and antidepressants for certain neuropathic pain conditions).

Available evidence insufficient to determine whether long-term opiate therapy for chronic pain results in sustained pain relief or improvements in function and quality of life or is superior to other pharmacologic or nonpharmacologic treatments. Use is associated with serious risks (e.g., opiate use disorder [OUD], overdose). (See Managing Opiate Therapy for Chronic Noncancer Pain under Dosage and Administration.)

Pain (Severe, Neuraxial Analgesia)

Used epidurally or intrathecally for relief of severe pain (neuraxial analgesia); administration of the drug by these routes reportedly provides pain relief for prolonged periods without attendant loss of motor, sensory, or sympathetic function.

Chronic epidural or intrathecal analgesia is indicated only when adequate pain relief cannot be obtained with less invasive therapies. The drug should only be administered epidurally or intrathecally by qualified individuals familiar with the techniques and patient management problems associated with these routes of morphine administration. (See Precautions Associated with Epidural or Intrathecal Administration under Cautions.)

Extended-release liposomal injection (DepoDur) is used epidurally for relief of severe pain following major surgery.

Pain (Acute Coronary Syndromes [ACS])

Relief of pain and anxiety related to ACS.

Considered analgesic agent of choice in patients with ST-segment-elevation MI (STEMI).

Considered reasonable in patients with non-ST-segment-elevation (NSTE) ACS who continue to experience pain despite treatment with maximally tolerated anti-ischemic drugs (e.g., nitrates). However, use of morphine should not preclude use of other anti-ischemic drugs with proven benefit.

Patients with acute MI typically exhibit overactivity of the sympathetic nervous system, which adversely increases myocardial oxygen demand via acceleration of heart rate, elevation in arterial blood pressure, augmentation of cardiac contractility, and heightened tendency to develop ventricular tachyarrhythmias. Principal objective in these patients is to administer sufficient doses of an analgesic such as morphine to relieve what many patients describe as a feeling of impending doom.

Analgesia during Labor

Used parenterally for analgesia during labor.

Acute Pulmonary Edema

Used in patients with acute pulmonary edema for its cardiovascular effects and to allay anxiety. Should not be used in the treatment of pulmonary edema resulting from a chemical respiratory irritant.

Neonatal Opiate Withdrawal

Has been used to manage manifestations of opiate abstinence syndrome (i.e., postnatal withdrawal) in neonates^{† [off-label]} exposed to opiates in utero.

Opiates recommended as first-line pharmacologic therapy when environmental and supportive measures (e.g., minimization of external stimuli, maximization of mother-infant contact [e.g., parental “rooming in”], breast-feeding when not contraindicated, swaddling and gentle handling) are inadequate. May add other adjunctive therapy (e.g., clonidine, phenobarbital) if response to opiates is inadequate or add phenobarbital if neonate was exposed to additional substances in utero.

Morphine has been used more extensively than other opiates in the management of neonatal opiate abstinence syndrome; however, some studies suggest methadone or buprenorphine treatment may be associated with shorter treatment durations and hospital stays. Additional study needed to establish optimal dosage schedules and preferred opiates and to evaluate longer-term (e.g., neurodevelopmental) outcomes.

Use of standardized protocols for identification, evaluation, and treatment recommended; use of protocols improves overall response, including shorter hospital stays and durations of pharmacologic treatment. Some evidence suggests that use of a standardized protocol may be more important than use of a specific opiate agonist (e.g., morphine versus methadone) in improving outcomes.

Related/similar drugs

gabapentin, acetaminophen, tramadol, cyclobenzaprine, naproxen, oxycodone, Tylenol

Morphine Dosage and Administration

General

Managing Opiate Therapy for Acute Pain

• Optimize concomitant use of other appropriate therapies.

• When opiate analgesia required, use conventional (immediate-release) opiates in smallest effective dosage and for shortest possible duration, since long-term opiate use often begins with treatment of acute pain.

• When sufficient for pain management, use lower-potency opiate analgesics given in conjunction with acetaminophen or an NSAIA on as-needed (“prn”) basis.

• Consider prescribing naloxone concomitantly for patients who are at increased risk of opiate overdosage or who have household members, including children, or other close contacts who are at risk for accidental ingestion or overdosage. (See Respiratory Depression under Cautions.)

• For acute pain not related to trauma or surgery, limit prescribed quantity to amount needed for expected duration of pain severe enough to require opiate analgesia (generally ≤3 days and rarely >7 days). Do not prescribe larger quantities for use in case pain continues longer than expected; instead, reevaluate patient if severe acute pain does not remit.

• For moderate to severe postoperative pain, provide opiate analgesic as part of a multimodal regimen that also includes acetaminophen and/or NSAIAs and other pharmacologic (e.g., certain anticonvulsants, regional local anesthetic techniques) and nonpharmacologic therapy as appropriate.

• Oral administration of conventional opiate analgesics generally preferred over IV administration in postoperative patients who can tolerate oral therapy.

• Scheduled (around-the-clock) dosing frequently is required during immediate postoperative period or following major surgery. When repeated parenteral administration is required, IV patient-controlled analgesia (PCA) generally is recommended.

Managing Opiate Therapy for Chronic Noncancer Pain

• Although specific recommendations may vary, common elements in clinical guideline recommendations include risk mitigation strategies, upper dosage thresholds, careful dosage titration, and consideration of risks associated with particular opiates and formulations, coexisting diseases, and concomitant drug therapy.

• Prior to initiating therapy, thoroughly evaluate patient; assess risk factors for misuse, abuse, and addiction; establish treatment goals (including realistic goals for pain and function); and consider how therapy will be discontinued if benefits do not outweigh risks.

• Regard initial opiate therapy for chronic noncancer pain as a therapeutic trial that will be continued only if there are clinically meaningful improvements in pain and function that outweigh treatment risks.

• Prior to and periodically during therapy, discuss with patients known risks and realistic benefits and patient and clinician responsibilities for managing therapy.

• Some experts recommend initiating opiate therapy for chronic noncancer pain with conventional (immediate-release) opiate analgesics prescribed at lowest effective dosage. Individualize opiate selection, initial dosage, and dosage titration based on patient’s health status, prior opiate use, attainment of therapeutic goals, and predicted or observed harms.

• Evaluate benefits and harms within 1–4 weeks following initiation of therapy or dosage increase and reevaluate on ongoing basis (e.g., at least every 3 months ) throughout therapy. Document pain intensity and level of functioning and assess progress toward therapeutic goals, presence of adverse effects, and adherence to prescribed therapies. Anticipate and manage common adverse effects (e.g., constipation, nausea and vomiting, cognitive and psychomotor impairment). If benefits do not outweigh harms, optimize other therapies and taper opiate to lower dosage or taper and discontinue opiate.

• When repeated dosage increases required, evaluate potential causes and reassess relative benefits and risks. Although evidence is limited, some experts state that opiate rotation may be considered in patients with intolerable adverse effects or inadequate benefit despite dosage increases.

• Higher dosages require particular caution, including more frequent and intensive monitoring or referral to specialist. Greater benefits of high-dose opiates for chronic pain not established in controlled clinical studies; higher dosages associated with increased risks (motor vehicle accidents, overdosage, OUD).

• CDC states that primary care clinicians should carefully reassess individual benefits and risks before prescribing morphine sulfate dosages ≥50 mg daily for chronic pain and should avoid dosages ≥90 mg daily or carefully justify decision to prescribe such dosages. Other experts recommend consulting a pain management specialist before exceeding a dosage of 80–120 mg daily. Some states have established opiate dosage thresholds (e.g., maximum daily dosages that can be prescribed, dosage thresholds at which consultation with specialist is mandated or recommended) or have mandated risk-management strategies (e.g., review of state prescription drug monitoring program [PDMP] data prior to prescribing).

• Recommended strategies for managing risks include written treatment agreements or plans (e.g., “contracts”), urine drug testing, review of state PDMP data, and risk assessment and monitoring tools.

• Taper and discontinue opiate therapy if patient engages in serious or repeated aberrant drug-related behaviors or drug abuse or diversion. Offer or arrange treatment for patients with OUD.

• Consider prescribing naloxone concomitantly for patients who are at increased risk of opiate overdosage or who have household members, including children, or other close contacts who are at risk for accidental ingestion or overdosage. (See Respiratory Depression under Cautions.)

Administration

Administered orally or rectally, by sub-Q, IM, or slow IV injection, or by IV infusion.

Administered epidurally or intrathecally (as a preservative-free injection; Astramorph/PF, Duramorph, Infumorph) via intermittent injection or continuous infusion. Also administered epidurally (as an extended-release liposomal injection; DepoDur) as a single dose.

IM is preferred to sub-Q injection when repeated parenteral doses are necessary, since repeated sub-Q injection causes local tissue irritation, pain, and induration. However, IM administration of opiate analgesics also is discouraged; IM injections can cause pain and are associated with unreliable absorption, resulting in inconsistent analgesia. Some experts state that IV injection or continuous IV or sub-Q infusion provides better comfort and reliability and that repeated IM injection should not be used routinely.

When morphine is administered IV, epidurally, or intrathecally, an opiate antagonist and facilities for administration of oxygen and control of respiration should be available.

Highly concentrated, conventional, preservative-free morphine sulfate injections intended for continuous epidural or intrathecal infusion via a controlled-microinfusion device (e.g., Infumorph 10 or 25 mg/mL) are not recommended for IV, IM, or sub-Q administration of individual doses of the drug because of the large amount of morphine sulfate contained in each ampul (200 mg/20 mL, 500 mg/20 mL) and the attendant risk of substantial overdosage.

Handle morphine sulfate injections carefully because of the potency of the injections; accidental cutaneous exposure should be treated by removing any contaminated clothing and rinsing the affected area with water.

Morphine sulfate injections are subject to substantial risk of overdosage if used inappropriately and to diversion and abuse; therefore, special control measures should be implemented within the institution, including restricted access, rigid accounting, and rigorous control of waste disposal.

Oral Administration

Administer orally as solution, conventional tablets, or extended-release preparations (Avinza capsules, Kadian capsules, MS-Contin tablets, Oramorph SR tablets).

Extended-release Preparations

Avinza or Kadian extended-release capsules and Oramorph SR extended-release tablets can be administered without regard to food; effect of food on GI absorption of MS-Contin extended-release tablets has not been fully evaluated to date.

Extended-release preparations should be swallowed intact and should not be broken, crushed, or chewed; intake of a broken, crushed, or chewed tablet may result in too rapid a release of the drug from the preparation and absorption of a potentially toxic dose of morphine sulfate. Do not administer extended-release capsules (Avinza, Kadian) with alcohol. (See Boxed Warning and see Specific Drugs under Interactions.)

Alternatively, the entire contents of Avinza or Kadian capsules may be sprinkled on a small amount of applesauce, at room temperature or cooler, immediately prior to administration; subdividing the contents of a capsule is not recommended. The beads or pellets should not be crushed, chewed, or dissolved. The patient should swallow the entire mixture and then drink a glass of water to rinse the mouth and ensure that the beads or pellets are swallowed. The mixture of applesauce and beads or pellets should not be stored for future use. (See Boxed Warning.)

Manufacturer of Kadian states that the contents of the extended-release capsules should not be administered through a nasogastric tube, but can be administered through a 16 French (16F) gastrostomy tube; consult manufacturer’s information.

Oral Solutions

Morphine sulfate oral solutions are commercially available in various concentrations, which generally are expressed in terms of mg of drug per mL (mg/mL) or per 5 mL (mg/5 mL) of solution. Serious adverse events and deaths have occurred as a result of inadvertent overdosage of concentrated morphine oral solutions. In most of these cases, morphine sulfate oral solutions prescribed in mg were mistakenly interchanged for mL of the concentrated preparation, resulting in 20-fold overdoses.

The 100-mg/5-mL concentration is indicated for use only in patients who are opiate tolerant (i.e., individuals who have been receiving ≥60 mg of oral morphine sulfate daily, ≥30 mg of oral oxycodone daily, ≥12 mg of hydromorphone hydrochloride daily, or an equianalgesic dosage of another opiate daily for ≥1 week) and have been titrated to a stable analgesic dosage using a preparation containing a lower concentration of morphine sulfate.

A graduated oral syringe is supplied by the manufacturer with the 100-mg/5-mL oral solution; always use this oral syringe to ensure that the dose is measured and administered accurately.

To avoid medication errors, write a prescription for morphine sulfate oral solution by clearly specifying the concentration of morphine sulfate oral solution to be dispensed and, in the directions for use, indicating the intended dose of morphine in mg along with the corresponding volume in mL (in parentheses).

It is important that the prescription be filled with the proper concentration of morphine sulfate oral solution to prevent potential medication errors; if the specified morphine sulfate oral solution is unavailable, pharmacists should contact the prescriber.

Provide careful instructions to patients receiving morphine oral solutions. (See Morphine Oral Solution under Advice to Patients.)

Rectal Administration

Administered rectally as suppositories.

Administer carefully according to manufacturer’s instructions.

IV Administration

For solution and drug compatibility information, see Compatibility under Stability.

Administer by direct IV injection or IV infusion. Also administered IV via a controlled-delivery device for PCA.

For IV injection, morphine sulfate should be injected slowly with the patient in the recumbent position. Rapid IV injection may result in an increased frequency of opiate-induced adverse effects; severe respiratory depression, apnea, hypotension, peripheral circulatory collapse, chest wall rigidity, cardiac arrest, and anaphylactoid reactions have occurred following rapid IV injection.

Dilution

For continuous IV infusion, morphine sulfate has been diluted to a concentration of 0.1–1 mg/mL in 5% dextrose and administered via a controlled-infusion device; more concentrated solutions have been used in patients whose fluid intake was restricted and/or dosage requirements were high.

Morphine sulfate injections containing 25 or 50 mg/mL are intended for preparation of IV infusion solutions and should not be administered IV without prior dilution.

For continuous sub-Q infusion^{† [off-label]}, the drug has been diluted to an appropriate concentration in 5% dextrose and administered via a portable, controlled, sub-Q infusion device.

Rate of Administration

The rate of continuous IV infusion of the drug must be individualized according to the response and tolerance of the patient.

Rate of IV infusion in neonates generally should not exceed 0.015–0.02 mg/kg per hour.

Epidural and Intrathecal Administration

Appropriate morphine sulfate solutions (e.g., solutions that do not contain preservatives [antioxidants, antimicrobial agents], alcohol, other neurotoxic ingredients, or any ingredient that could compromise the safety and performance of the infusion pump [when continuous-infusion therapy is employed]; recommended pH of the solution is 4–8) (e.g., Astramorph/PF, Duramorph, Infumorph) may be given epidurally or intrathecally by intermittent administration or by continuous infusion (e.g., via an implantable controlled-infusion device such as an Infusaid or SynchroMed pump) if necessary.

Highly concentrated, preservative-free morphine sulfate solutions for epidural or intrathecal use (e.g., Infumorph 10 or 25 mg/mL) are intended for use via continuous, controlled-microinfusion devices. Such injections should not be used for individual-dose epidural or intrathecal injection since less-concentrated, preservative-free injections can be employed more reliably for the small doses required.

Morphine sulfate extended-release liposomal injection (DepoDur) is administered epidurally.

Specialized techniques are required for epidural or intrathecal administration of morphine sulfate; the drug should be administered via these routes only by qualified individuals familiar with the techniques of administration and patient management problems associated with these routes of morphine administration. (See Precautions Associated with Epidural or Intrathecal Administration under Cautions.)

When the drug is injected epidurally or intrathecally as individual doses, the patient should be in a setting where adequate monitoring is possible. Because delayed respiratory depression can occur, patient monitoring should be continued for ≥24 hours after each dose of morphine sulfate injection or for ≥48 hours after a dose of morphine sulfate extended-release liposomal injection (DepoDur).

Facilities, drugs, and equipment necessary for the management of inadvertent intravascular injection during attempted epidural or intrathecal injection should be readily available.

Because epidural administration of the drug has been associated with a lower potential for immediate and delayed adverse effects than intrathecal administration, the epidural rather than intrathecal route should be used whenever possible.

Epidural or intrathecal administration should be limited to the lumbar region since administration in the thoracic region has been associated with a substantially increased frequency of early and late respiratory depression even at low doses.

Because the intrathecal dose of morphine is ¹/₁₀ the epidural dose, the risk of overdose from inadvertent intrathecal injection during attempted epidural injection should be considered and facilities, drugs, and equipment for treating morphine overdose should be readily available.

Epidural or Intrathecal Administration (Morphine Sulfate Injection)

For epidural administration, the appropriate dose of the drug is injected into the epidural space after proper placement of the needle or catheter has been verified.

For intrathecal administration, no more than 2 or 1 mL of the injection containing 0.5 or 1 mg/mL, respectively, should be injected intrathecally.

The safety of injecting repeated intermittent doses of the drug intrathecally, other than for establishing initial dosage when continuous intrathecal infusion is contemplated, has not been determined and, if pain recurs and additional morphine therapy is required for patients who are not candidates for such infusion, alternative routes of administration should be considered.

If the highly concentrated injections intended for such administration (e.g., Infumorph) are used, an implantable controlled-microinfusion device is used.

Dilution of the highly concentrated injections may be necessary, depending on the infusion device employed and/or individual dosage requirements; 0.9% sodium chloride injection is recommended for dilution.

Filling of the drug reservoir of the device should be performed only by fully trained and qualified personnel, following the directions provided by the device’s manufacturer.

Care should be taken in employing the proper refill frequency so that depletion of the reservoir during use is avoided.

Extreme caution must be employed to ensure proper placement of the syringe needle in the filling port of the device prior to refilling the reservoir; inadvertent injection outside the filling port, into the tissue surrounding the device, or, in the case of multiport devices, into a port intended for single supplementary doses could result in large, clinically important overdosage. Severe, potentially life-threatening respiratory depression could result from technical errors during refill.

Patients and/or their attendants should be instructed in proper home care of the device and the insertion site and in the recognition and practical treatment of epidural or intrathecal morphine overdosage.

Epidural Administration (Morphine Sulfate Extended-release Liposomal Injection)

The extended-release liposomal injection (DepoDur) may be administered undiluted or diluted up to 5 mL total volume with preservative-free 0.9% sodium chloride injection.

Just before withdrawal of a dose from the vial, gently invert the vial to resuspend the particles. Avoid aggressive agitation. Administer dose within 4 hours after withdrawal from the vial. Do not administer using an inline filter; do not admix with other drugs, including local anesthetics. Do not administer any other drug into the epidural space for at least 48 hours.

If a test dose of lidocaine 1.5% and epinephrine 1:200,000 is used to verify catheter placement, flush catheter after the test dose and allow ≥15 minutes to elapse before administering morphine sulfate extended-release liposomal injection. (See Specific Drugs under Interactions.)

Dosage

Available as morphine sulfate; dosage usually expressed as the sulfate.

Use lowest effective dosage and shortest duration of therapy consistent with treatment goals of the patient.

When switching patients receiving chronic opiate therapy from one opiate analgesic to another, generally reduce the calculated equianalgesic dosage of the new opiate agonist by about 25–50% to avoid inadvertent overdosage. This calculation does not apply when switching to methadone; consult specific recommendations for methadone dosage.

When used concomitantly with other CNS depressants, use lowest effective dosages and shortest possible duration of concomitant therapy. (See Specific Drugs under Interactions.)

Pediatric Patients

Pain

Moderate to Severe Pain

Oral

Infants and children: 0.2–0.5 mg/kg every 4–6 hours (conventional tablets, oral solution).

IM or Sub-Q

Neonates: 0.05–0.2 mg/kg every 2–4 hours as necessary.

Infants and children: 0.1–0.2 mg/kg every 2–4 hours.

Single pediatric doses should not exceed 10 mg.

IV

Neonates: 0.05–0.2 mg/kg every 2–4 hours as necessary. For continuous IV infusion, 0.025–0.05 mg/kg per hour.

Infants and children: 0.1–0.2 mg/kg every 2–4 hours.

Adolescents >12 years of age: 3–4 mg; may repeat in 5 minutes if needed.

Single pediatric doses should not exceed 10 mg.

PCA (usually IV) via controlled-delivery device: Loading doses of 0.05 mg/kg (preferably titrated by clinician or nurse at bedside, up to 0.05–0.2 mg/kg total) used. Maintenance doses (administered intermittently) of 10–20 mcg/kg, usually no more frequently than every 6–12 minutes as a device-programmed lockout period used for developmentally mature pediatric patients ≥7 years of age.

Epidural or Intrathecal

Safety and efficacy in children not established.

Cancer Pain (Severe, Chronic)

IV

Maintenance dosages of 0.025–2.6 mg/kg per hour (median: 0.04–0.07 mg/kg per hour) have been infused IV in children.

Sub-Q

Maintenance dosages of 0.025–1.79 mg/kg per hour (median: 0.06 mg/kg per hour) have been infused sub-Q in a limited number of children.

Sickle Cell Crisis (Severe Pain)

IV

Maintenance dosages of 0.03–0.15 mg/kg per hour have been infused IV in children.

Postoperative Analgesia

IV

Maintenance dosages of 0.01–0.04 mg/kg per hour have been infused.

Neonatal Opiate Withdrawal† [off-label]

Oral

Use standardized protocols that base initiation, adjustment, and tapering of dosage on standardized patient assessments performed at regular intervals (e.g., Finnegan scoring system [original or modified versions] performed every 3–4 hours).

Treatment protocols vary in recommended dosages, thresholds for treatment initiation, incremental changes and thresholds for dosage adjustment, and tapering strategies. Further study needed to define optimal strategies.

Under various protocols, treatment initiated at a dosage of 0.04–0.05 mg/kg (as oral solution) every 3–4 hours based on Finnegan score (e.g., score >8 on 2 or 3 occasions, sum of 3 consecutive scores ≥24, 1 score or 2 consecutive scores ≥12); under other protocols, initial dosage may vary depending on severity of withdrawal, with higher initial dosages recommended for neonates with higher Finnegan scores. Some clinicians state usual initial dosage is 0.03–0.1 mg/kg every 3–4 hours.

If Finnegan score remains elevated (e.g., 1 score or 2 consecutive scores ≥12, 2 consecutive scores ≥8, sum of 3 scores ≥24 ), increase dosage, generally by 0.02–0.05 mg/kg per dose or by 10–20% depending on the protocol and/or Finnegan score, to achieve stabilization. Some clinicians recommend usual maximum dosage of 1.2–1.3 mg/kg daily or 0.2 mg/kg per dose.

Once patient is stable (generally, no score >8 ) for ≥48 hours, taper dosage, typically in decrements of approximately 0.02 mg/kg per dose or approximately 10% of the highest (stabilization) dose at intervals of approximately 24–48 hours. Dosage at which morphine is discontinued varies by protocol.

Monitor neonate for ≥48 hours after morphine is discontinued.

Consult specialized protocols for further information on dosage and monitoring of Finnegan scores.

Adults

Pain (Oral Treatment)

Most manufacturers suggest that it is preferable to initiate and stabilize oral morphine sulfate therapy with a conventional (immediate-release) preparation and then switch the patient to an extended-release preparation (Avinza, Kadian, MS Contin, Oramorph SR) since titration of dosage may be more difficult with the latter preparations.

Dosing regimen must be individualized based on the patient’s prior analgesic therapy.

Initial dosage of extended-release preparations should be based on the total daily dosage, potency, and specific characteristics of the current opiate agonist.

Other considerations should include the reliability of relative potency estimates used in calculating the equivalent morphine sulfate dosage, the degree of opiate experience and tolerance, the medical condition of the patient, concomitant drug therapy, and the nature and severity of the patient’s pain.

It is preferable to underestimate the initial dosage of extended-release preparations than to inadvertently cause an overdosage of morphine sulfate.

Supplemental doses of a short-acting opiate agonist can be considered if breakthrough pain occurs with dosing regimens employing extended-release preparations.

When converting to another oral extended-release morphine sulfate preparation or to other oral or parenteral opiate analgesics, the manufacturer’s labeling information should be consulted.

Oral Solutions or Conventional Tablets

Oral

Usually, 10–30 mg every 4 hours as necessary or as directed by a physician.

Extended-release Capsules (Avinza)

Oral

Individualize dosage according to patient response and tolerance; do not exceed 1.6 g daily. (See Fumaric Acid under Cautions.)

Administer Avinza no more frequently than once every 24 hours. The 60-, 90-, and 120-mg Avinza capsules should be used only in opiate-tolerant patients.

Switching from other oral morphine preparations to Avinza: Use the prior total daily oral dosage and administer once every 24 hours. Supplemental doses of a short-acting opiate analgesic may be required for up to 4 days until the patient’s response to Avinza has stabilized.

Switching from parenteral morphine or other non-morphine oral or parenteral opiate therapy to Avinza: Calculate the opiate analgesic requirements during the previous 24 hours and convert to an equianalgesic dosage of Avinza. Use conservative dosage conversion ratios to avoid toxicity.

When used as the initial opiate in patients who do not have a proven tolerance to opiates: Usual initial dosage is 30 mg once daily; increase dosage by no more than 30 mg every 4 days. Dosage increases should be conservative in opiate-naive patients.

Extended-release Capsules (Kadian)

Oral

Individualize dosage according to patient response and tolerance; do not increase dosage more frequently than every other day.

Administer Kadian no more frequently than every 12 hours. Patients receiving once-daily Kadian who experience excessive sedation or inadequate analgesia prior to the next dose should be switched to a twice-daily regimen. The 100- and 200-mg Kadian capsules should be used only in opiate-tolerant patients.

Switching from other oral morphine preparations to Kadian: Use the prior total daily oral dosage and give in 2 divided doses every 12 hours or once every 24 hours. First dose of Kadian may be administered concurrently with the last dose of immediate-release opiate therapy because of the delayed peak plasma morphine concentrations produced by Kadian.

Switching from parenteral morphine or other non-morphine oral or parenteral opiate therapy to Kadian: Calculate the opiate analgesic requirements during the previous 24 hours and convert to an equianalgesic dosage of Kadian. Use conservative dosage conversion ratios to avoid toxicity.

When used as the initial opiate in patients who do not have a proven tolerance to opiates: Initially 10 or 20 mg of Kadian; increase by no more than 20 mg every other day.

Extended-release Tablets (MS Contin)

Oral

Individualize dosage according to patient response and tolerance.

Interval between doses of MS Contin should not exceed 12 hours in order to avoid administration of large single doses.

Use 15-mg tablets when total daily dosage is expected to be <60 mg daily; use 30-mg tablets when total daily dosage is expected to be 60–120 mg daily. The 100- and 200-mg tablets of MS Contin should be used only in patients who are opiate tolerant and require dosages of ≥200 mg daily.

Switching from an immediate-release oral morphine preparation to MS Contin: Use the prior total daily oral dosage and give in 2 divided doses every 12 hours or in 3 divided doses every 8 hours.

Switching from parenteral morphine or other oral or parenteral non-morphine opiate to MS Contin: Calculate the opiate analgesic requirements during the previous 24 hours and convert to an equianalgesic dosage of MS Contin. Use conservative dosage conversion ratios to avoid toxicity.

Extended-release Tablets (Oramorph SR)

Oral

Individualize dosage according to patient response and tolerance.

Dosing interval for Oramorph SR should not exceed 12 hours because administration of large single doses may lead to acute overdosage. If pain is not controlled for the entire 12-hour interval, then the dosing interval may be decreased, but doses should be administered no more frequently than every 8 hours.

Use 30-mg tablets if morphine sulfate requirement is ≤120 mg daily. Use 15-mg tablets if morphine sulfate requirement is low.

Switching from other oral morphine preparations to Oramorph SR: Use the prior total daily oral dosage and give in 2 divided doses every 12 hours.

Switching from parenteral morphine or other oral or parenteral non-morphine opiate to Oramorph SR: Calculate the opiate analgesic requirements during the previous 24 hours and convert to an equianalgesic dosage of Oramorph SR. Use conservative dosage conversion ratios to avoid toxicity.

Pain (Other Routes)

Rectal

Suppositories: Usually, 10–20 mg every 4 hours as necessary or as directed by a physician.

IV

May administer 2.5–20 mg every 2–6 hours as needed or via continuous infusion at a rate of 0.8–10 mg per hour.

Can be administered at a rate of 2–4 mg every 5 minutes, with some patients requiring as much as 25–30 mg before pain relief is adequate.

IM or Sub-Q

May administer 2.5–20 mg every 2–6 hours as needed or via continuous infusion at a rate of 0.8–10 mg per hour.

Epidural (Morphine Sulfate Injection [preservative-free])

Usual initial dose for intermittent injection is 5 mg.

Inadequate pain relief within 1 hour after administration of the initial dose: Additional epidural doses may be given carefully in 1- to 2-mg increments at intervals sufficient to assess efficacy; no more than 10 mg total daily dose.

Pain relief generally occurs within 6–30 minutes and persists for about 16–24 hours (range: 4–36 hours) after a single, effective epidural dose of morphine.

Continuous epidural infusion, device not implanted surgically: Initial dosage of 2–4 mg per 24 hours has been recommended; epidural dosage may be increased by 1–2 mg daily if adequate relief is not achieved initially.

If an implantable microinfusion device is to be employed for continuous epidural infusion, efficacy and adverse effects of initial dosage should be assessed for each patient using serial, intermittent epidural doses of the drug prior to implantation surgery.

Most adults who are not tolerant to opiates achieve adequate relief with initial epidural dosages of 3.5–7.5 mg daily.

Administer with extreme caution and in reduced dosage epidurally or intrathecally in geriatric or debilitated patients.

Epidural (Morphine Sulfate Extended-release Liposomal Injection [DepoDur])

Administer as a single dose.

Major orthopedic surgery of a lower extremity: 15 mg prior to surgery. Some patients may benefit from 20-mg dose; however, the incidence of serious adverse respiratory events was dose related in studies.

Lower abdominal or pelvic surgery: 10–15 mg prior to surgery. Some patients may benefit from 20-mg dose; however, the incidence of serious adverse respiratory events was dose related in studies.

Cesarean section: 10 mg after the umbilical cord is clamped.

Intrathecal

The intrathecal dose of morphine sulfate is about ¹/₁₀ the epidural dose.

A single 0.2- to 1-mg intrathecal dose may provide adequate relief for up to 24 hours in adults who are not tolerant to opiates.

Repeated intrathecal doses of the drug are not recommended except to establish initial intrathecal dosage when continuous intrathecal infusion is to be employed; if additional morphine therapy is necessary for patients who are not candidates for continuous intrathecal infusion, alternative routes of administration should be considered.

Naloxone may be infused IV at a rate of 0.6 mg/hour for 24 hours after intrathecal morphine administration to decrease potential opiate-induced adverse effects.

If an implantable microinfusion device is to be employed for continuous intrathecal infusion, efficacy and adverse effects of initial dosage should be assessed for each patient using serial, intermittent intrathecal doses of the drug prior to implantation surgery.

Intrathecal dosages exceeding 20 mg daily should be employed with caution since they may be associated with an increased likelihood of serious toxicity, including myoclonic spasms.

Administer with extreme caution and in reduced dosage epidurally or intrathecally in geriatric or debilitated patients.

Pain (ACS)

IV

To relieve pain in adults with STEMI, an initial dose of 4–8 mg is recommended; may administer additional doses of 2–8 mg every 5–15 minutes as needed.

In patients with NSTE ACS who continue to experience pain despite maximally tolerated anti-ischemic therapy, a dose of 1–5 mg IV may be administered during IV nitroglycerin therapy; may repeat every 5–30 minutes to relieve symptoms and maintain patient comfort.

Cancer Pain

Individualize dosage according to the response and tolerance of the patient for sub-Q or continuous IV infusions.

Continuous IV

Initially 0.8–10 mg/hour and then increase to an effective dosage as necessary; an IV loading dose of ≥15 mg can be administered for initial relief of pain prior to initiating continuous IV infusion of the drug.

Maintenance doses have ranged from 0.8–80 mg/hour infused IV, although higher (e.g., 150 mg/hour) maintenance dosages occasionally have been required.

Patient-controlled Analgesia (PCA)

IV

Adjust dosage according to the severity of the pain and response of the patient; consult the operator’s manual for the patient-controlled infusion device for directions on administering the drug at the desired rate of infusion.

Exercise care to avoid overdosage, which could result in respiratory depression, or abrupt cessation of therapy with the drug, which could precipitate opiate withdrawal.

PCA via controlled-delivery device: Standard protocol uses loading dose of 1 mg, time between doses of 6 minutes (lockout period), and limit of 10 doses per hour. Loading doses of 2–4 mg every 10 minutes, preferably titrated by clinician or nurse at bedside, up to 6–16 mg total have been used for rapid control of pain. Maintenance doses (self-administered intermittently) of 0.5–2 mg, usually no more frequently than every 6–12 minutes as a device-programmed lockout period used.

Unstable Angina (Unresponsive to 3 Sublingual Doses of Nitroglycerin)

IV

2–5 mg (repeated every 5–30 minutes as needed to relieve symptoms and maintain patient comfort) has been used.

Analgesia during Labor

Sub-Q or IM

10 mg.

Prescribing Limits

Pediatric Patients

Analgesia

Moderate to Severe Pain

IV, IM, or Sub-Q

Single pediatric doses should not exceed 15 mg.

Adults

Analgesia

For acute pain not related to trauma or surgery, limit prescribed quantity to amount needed for the expected duration of pain severe enough to require opiate analgesia (generally ≤3 days and rarely >7 days).

CDC recommends that primary care clinicians carefully reassess individual benefits and risks before prescribing morphine sulfate dosages ≥50 mg daily for chronic pain and avoid dosages ≥90 mg daily or carefully justify their decision to prescribe such dosages. Other experts recommend consulting a pain management specialist before exceeding a dosage of 80–120 mg daily.

Some states have set prescribing limits (e.g., maximum daily dosages that can be prescribed, dosage thresholds at which consultation with a specialist is mandated or recommended).

Avinza

Oral

Do not exceed 1.6 g daily. (See Fumaric Acid under Cautions.)

Administer no more frequently than every 24 hours. Increase dosage by no more than 30 mg every 4 days.

Kadian

Oral

Administer no more frequently than every 12 hours.

MS Contin

Oral

Interval between doses should not exceed 12 hours in order to avoid administration of large single doses.

Oramorph SR

Oral

Dosing interval should not exceed 12 hours because administration of large single doses may lead to acute overdosage.

Administer no more frequently than every 8 hours.

Analgesia

Intrathecal

Intrathecal dosages exceeding 20 mg daily should be employed with caution since they may be associated with an increased likelihood of serious toxicity, including myoclonic spasms.

Special Populations

Reduced dosage is indicated in poor-risk patients, in patients with substantial hepatic impairment, and in very young or very old patients.

Hepatic Impairment

Reduce dosage in patients with severe hepatic impairment.

Renal Impairment

Reduce dosage in patients with severe renal impairment, since the active metabolite morphine 6-glucuronide accumulates in such patients which can result in enhanced and prolonged opiate activity.

Geriatric and Debilitated Patients

Reduce dosage in poor-risk patients and in very old patients.

Administer epidurally or intrathecally with extreme caution and in reduced dosage in geriatric or debilitated patients.

Cautions for Morphine

Contraindications

• Hypersensitivity to morphine, morphine salts, or any ingredient in the formulation.

• Respiratory depression in the absence of resuscitative equipment.

• Acute or severe bronchial asthma or hypercarbia.

• Known or suspected paralytic ileus.

• Epidural or intrathecal injection contraindicated in patients whose concomitant drug therapy or medical condition would contraindicate administration of the drug by these routes, such as when infection is present at the injection site or when the patient has uncontrolled bleeding diathesis or is receiving anticoagulants.

• Extended-release liposomal injection (DepoDur) also contraindicated in patients in circulatory shock.

Warnings/Precautions

Warnings

Respiratory Depression

The major toxicity associated with morphine.

Occurs most frequently in geriatric and debilitated patients, and those with conditions accompanied by hypoxia or hypercapnia when even moderate therapeutic doses may dangerously decrease pulmonary ventilation.

May be severe, requiring maintenance of an adequate airway, use of resuscitative equipment, and administration of oxygen, an opiate antagonist, and/or other resuscitative drugs.

Use with extreme caution in patients with COPD or cor pulmonale, and in patients having a substantially decreased respiratory reserve, hypoxia, hypercapnia, or preexisting respiratory depression. In such patients, even therapeutic morphine doses may decrease respiratory drive while simultaneously increasing airway resistance to the point of apnea.

Bolus epidural or intrathecal administration may result in early respiratory depression because of direct venous redistribution of the drug to the respiratory centers in the CNS. Late (up to 24 hours) acute respiratory depression also has occurred following epidural or intrathecal administration of morphine sulfate injection and is thought to result from rostral spread of the drug in the CNS. Delayed respiratory depression (≥ 48 hours) may occur following administration of morphine sulfate extended-release liposomal injection (DepoDur). Risk of respiratory depression may be increased if the surgical procedure is cancelled after administration of the extended-release liposomal injection; monitor carefully. Respiratory depression requiring administration of naloxone or ventilatory support reported following intrathecal administration of DepoDur. (See Precautions Associated with Epidural or Intrathecal Administration under Cautions.)

Intrathecal administration has been associated with a higher incidence of respiratory depression than epidural administration. A diminished CO₂ ventilatory response may be present for up to 22 hours following epidural or intrathecal administration of the drug, despite the absence of clinical evidence of inadequate ventilation.

In patients receiving chronic epidural or intrathecal therapy, monitor patients in an adequately equipped (e.g., resuscitative equipment, oxygen, an opiate antagonist and other resuscitative drugs) and staffed environment (hospitalization is recommended) for ≥24 hours after administration of an initial test dose and, as appropriate, for several days after catheter implantation for additional monitoring and dosage adjustment. An opiate antagonist and resuscitative equipment also should be immediately available whenever the reservoir of the microinfusion device is being refilled with morphine sulfate or is being otherwise manipulated.

In patients receiving morphine sulfate extended-release liposomal injection (DepoDur), monitor patients in an adequately equipped (e.g., resuscitative equipment, oxygen, an opiate antagonist and other resuscitative drugs) and staffed environment for ≥48 hours after administration of the dose.

Routinely discuss availability of the opiate antagonist naloxone with all patients receiving new or reauthorized prescriptions for opiate analgesics, including morphine.

Consider prescribing naloxone for patients receiving opiate analgesics who are at increased risk of opiate overdosage (e.g., those receiving concomitant therapy with benzodiazepines or other CNS depressants, those with history of opiate or substance use disorder, those with medical conditions that could increase sensitivity to opiate effects, those who have experienced a prior opiate overdose) or who have household members, including children, or other close contacts who are at risk for accidental ingestion or overdosage. Even if patients are not receiving an opiate analgesic, consider prescribing naloxone if the patient is at increased risk of opiate overdosage (e.g., those with current or past diagnosis of OUD, those who have experienced a prior opiate overdose).

Concomitant Use with Benzodiazepines or Other CNS Depressants

Concomitant use of opiates, including morphine, and benzodiazepines or other CNS depressants (e.g., anxiolytics, sedatives, hypnotics, tranquilizers, muscle relaxants, general anesthetics, antipsychotics, other opiate agonists, alcohol) may result in profound sedation, respiratory depression, coma, and death. Substantial proportion of fatal opiate overdoses involve concurrent benzodiazepine use.

Reserve concomitant use of morphine and other CNS depressants for patients in whom alternative treatment options are inadequate. (See Specific Drugs under Interactions.)

Adrenal Insufficiency

Adrenal insufficiency reported in patients receiving opiate agonists or opiate partial agonists. Manifestations are nonspecific and may include nausea, vomiting, anorexia, fatigue, weakness, dizziness, and hypotension.

If adrenal insufficiency is suspected, perform appropriate laboratory testing promptly and provide physiologic (replacement) dosages of corticosteroids; taper and discontinue the opiate agonist or partial agonist to allow recovery of adrenal function. If the opiate agonist or partial agonist can be discontinued, perform follow-up assessment of adrenal function to determine if corticosteroid replacement therapy can be discontinued. In some patients, switching to a different opiate improved symptoms.

Head Injury and Increased Intracranial Pressure

The respiratory depressant effects of morphine (with CO₂ retention and secondary elevation of CSF pressure) may be markedly exaggerated in the presence of head injury, other intracranial lesions, or preexisting increase in intracranial pressure.

Morphine produces effects (e.g., pupillary changes) that may obscure neurologic signs of further increase in pressure in patients with head injuries.

May interfere with evaluation of CNS function, and respiratory depression produced by the drug may produce cerebral hypoxia and elevated CSF pressure not caused by the injury itself.

Use with extreme caution, if at all, in patients with severe CNS depression, anoxia, hypercapnia, or respiratory depression or those who are especially prone to respiratory depression such as comatose patients or those with head injury, brain tumor, or elevated CSF pressure. Avoid use of morphine sulfate extended-release liposomal injection (DepoDur) in patients with head injury or increased intracranial pressure.

Hypotensive Effects

Like all opiate analgesics, may cause severe hypotension in individuals whose ability to maintain their BP is compromised by depleted blood volume or concomitant drugs (e.g., phenothiazines, general anesthetics). Consider avoiding concomitant use of vasodilators. (See Specific Drugs under Interactions.)

May produce orthostatic hypotension in ambulatory patients.

Orthostatic hypotension is a frequent complication of single-dose epidural or intrathecal morphine therapy, and patients with reduced circulatory volume or impaired myocardial function and those receiving sympatholytic therapy may be at particular risk.

Use the minimal effective dose; patient’s legs should be elevated to decrease the possibility of hypotension.

Use with caution in patients in circulatory shock, since vasodilation produced by the drug may further reduce cardiac output and BP. Morphine sulfate extended-release liposomal injection (DepoDur) is contraindicated in patients in circulatory shock.

Dependence and Abuse

Physical and psychic dependence and tolerance may develop with repeated administration, and abuse potential exists; use with caution. Clinicians should consider abuse potential when prescribing or dispensing morphine in situations where they are concerned about an increased risk of misuse, abuse, or diversion. However, concerns about abuse, addiction, and diversion should not prevent the proper management of pain.

Abrupt cessation of therapy or sudden reduction in dosage after prolonged use may result in withdrawal symptoms. After prolonged exposure to opioid analgesics, if withdrawal is necessary, it must be undertaken gradually.

Health-care professionals should contact the professional licensing board or controlled substance authority in their states for information about prevention and detection of abuse or diversion.

Prolonged maternal use of opiates during pregnancy can result in neonatal opiate withdrawal syndrome. (See Pregnancy under Cautions.)

Acute Abdominal Conditions

Administration may complicate assessment of patients with acute abdominal conditions.

Can diminish propulsive peristaltic waves in the GI tract and may prolong the obstruction.

In patients with GI obstruction, especially paralytic ileus, oral extended-release preparation may remain in the stomach for a prolonged period and subsequently release a bolus of morphine when normal gut motility is restored.

Contraindicated in patients with known or suspected paralytic ileus.

Myoclonic Spasms

Myoclonic spasms of skeletal muscle have been reported; treatment of opiate intoxication may be required in some cases.

In some patients, resumption of therapy after appropriate management of the toxicity may be possible at reduced dosage and/or by replacement of epidural with intrathecal therapy.

Concentrated Morphine Oral Solutions

Serious adverse events and deaths have occurred as a result of inadvertent overdosage of concentrated morphine sulfate oral solutions. (See Risk of Medication Errors with Oral Solutions in Boxed Warning.)

In most cases, morphine sulfate oral solutions prescribed in mg were mistakenly interchanged for mL of the concentrated preparation, resulting in 20-fold overdoses.

Morphine sulfate 100-mg/5-mL oral solution is indicated for use only in patients who are opiate tolerant (i.e., individuals who have been receiving ≥60 mg of oral morphine sulfate daily, ≥30 mg of oral oxycodone daily, ≥12 mg of hydromorphone hydrochloride daily, or an equianalgesic dosage of another opiate daily for ≥1 week) and have been titrated to a stable analgesic dosage using a preparation containing a lower concentration of morphine sulfate.

It is important that prescriptions for morphine sulfate oral solution be written clearly and filled with the proper concentration of morphine sulfate oral solution to prevent potential medication errors. (See Oral Solutions under Dosage and Administration.)

Sensitivity Reactions

Hypersensitivity Reactions

Anaphylaxis reported rarely.

Sulfite Sensitivity

Some commercially available formulations of morphine sulfate injection contain sulfites that may cause allergic-type reactions, including anaphylaxis and life-threatening or less severe asthmatic episodes, in certain susceptible individuals.

Overall prevalence of sulfite sensitivity in the general population is unknown but probably low; such sensitivity appears to occur more frequently in asthmatic than in nonasthmatic individuals.

General Precautions

Fumaric Acid

Avinza extended-release capsules contain fumaric acid.

Safety of morphine sulfate dosages >1.6 g daily administered as Avinza extended-release capsules has not been established; such dosages contain a quantity of fumaric acid that may be associated with serious renal toxicity.

Precautions Associated with Epidural or Intrathecal Administration

Epidural and intrathecal administration of morphine frequently associated with dose-related pruritus; not necessarily confined to the site of administration.

Urinary retention, which may persist for 10–20 hours after administration, has occurred in about 90% of males who received the drug epidurally or intrathecally and less frequently in females. Early recognition of urinary difficulty and prompt intervention in cases of retention are important, particularly in patients with prostatic enlargement.

In addition to the usual precautions associated with morphine use, for epidural or intrathecal administration, the drug should only be used by qualified individuals familiar with the techniques of administration and patient management problems associated with these routes of administration.

Because chronic epidural or intrathecal therapy employing a controlled-microinfusion device is accompanied by considerable patient risk and requires a high level of skill to be accomplished successfully, such therapy should only be undertaken by experienced clinical teams who are well informed about patient selection criteria, evolving technology, and emerging standards of care.

Safety of intrathecal administration of morphine sulfate extended-release liposomal injection (DepoDur) not evaluated; this preparation is intended for administration by the epidural route. (See Respiratory Depression under Cautions.)

CNS Effects

May impair mental and/or physical abilities needed to perform potentially hazardous activities such as driving or operating machinery. Individuals who perform hazardous tasks requiring mental alertness or physical coordination should be warned about possible adverse CNS effects of opiate agonists.

High doses may result in seizures. Monitor patients with known seizure disorder for seizure activity; increased risk of seizures in these individuals.

Hypothyroidism

Use with caution and in reduced dosage in patients with hypothyroidism.

Prostatic Hypertrophy or Urethral Stricture

Use with caution and in reduced dosage in patients with prostatic hypertrophy or urethral stricture.

Pancreatic and Biliary Disease

May cause spasm of the sphincter of Oddi. Use with caution in patients with biliary tract disease, including acute pancreatitis, and patients undergoing biliary tract surgery. Opiates may increase serum amylase concentrations.

Addison’s Disease

Use with caution and in reduced dosage in patients with Addison’s disease.

Cordotomy

Patients taking Kadian extended-release capsules who are scheduled for cordotomy or other interruption of pain transmission pathways should discontinue the drug 24 hours prior to the procedure and pain should be controlled by parenteral short-acting opiates. In addition, the post-procedure titration of analgesics for such patients should be individualized to avoid either oversedation or withdrawal syndromes.

Cardiac Arrhythmia

May increase ventricular response rate through a vagolytic action; use with caution in patients with atrial flutter and other supraventricular tachycardias.

Possible Prescribing and Dispensing Errors

Ensure accuracy of prescription; similarity in spelling of Kadian and Kapidex (former trade name for dexlansoprazole, a proton-pump inhibitor) may result in errors.

Hypogonadism

Hypogonadism or androgen deficiency reported in patients receiving long-term opiate agonist or opiate partial agonist therapy; causality not established. Manifestations may include decreased libido, impotence, erectile dysfunction, amenorrhea, or infertility. Perform appropriate laboratory testing in patients with manifestations of hypogonadism.

Specific Populations

Pregnancy

Category C.

Although morphine has been used during labor, use of opiate agonists generally should be avoided during labor when delivery of a premature neonate is anticipated. (See Pediatric Use under Cautions.)

Because maternally administered opiate agonists are readily distributed into fetal circulation, an opiate antagonist and resuscitative equipment for reversal of opiate-induced respiratory depression should be readily available when the drugs are used during labor and delivery.

Epidurally and intrathecally administered morphine also is readily distributed into fetal circulation and may result in respiratory depression in the neonate.

Controlled clinical studies have shown that epidurally administered morphine has little or no effect on labor pain.

Morphine sulfate extended-release liposomal injection (DepoDur) may be used during cesarean section after the umbilical cord is clamped but should not be used during labor and/or vaginal delivery.

Prolonged maternal use of opiates during pregnancy can result in neonatal opiate withdrawal syndrome; in contrast to adults, withdrawal syndrome in neonates may be life-threatening and requires management according to protocols developed by neonatology experts. Syndrome presents with irritability, hyperactivity and abnormal sleep pattern, high-pitched cry, tremor, vomiting, diarrhea, and failure to gain weight. Onset, duration, and severity vary depending on specific opiate used, duration of use, timing and amount of last maternal use, and rate of drug elimination by the neonate. Ensure availability of appropriate treatment. (See Neonatal Opiate Withdrawal under Uses.)

Lactation

Distributed into milk; use with caution. When morphine sulfate extended-release liposomal injection (DepoDur) is used during cesarean section, decide whether or not to allow nursing during the first 48 hours.

Pediatric Use

Safety and efficacy of conventional oral preparations (solution, tablets) not established in children.

Safety and efficacy of extended-release oral preparations not established in children <18 years of age.

Opiate agonists generally should not be used in premature neonates since the drugs reportedly cross the immature blood-brain barrier more readily than they do the mature barrier and thereby produce disproportionate respiratory depression.

Opiate agonists should be administered with caution and in carefully determined dosages to infants and small children since they may be relatively more sensitive to opiates on a body-weight basis.

Safety and efficacy of epidural or intrathecal administration in children have not been determined and these routes are not recommended.

Geriatric Use

Clinical studies of extended-release oral preparations did not include sufficient numbers of patients ≥65 years of age to determine whether they respond differently than younger adults.

Because of the greater frequency of decreased hepatic, renal, and/or cardiac function and of concomitant disease and drug therapy in geriatric patients, use extended-release oral preparations with caution in this age group and select dosage at the lower end of the dosage range.

The pharmacodynamics of epidurally or intrathecally administered morphine are more variable in geriatric patients than in younger adults. Considerable interindividual variation in effective initial dosage, rate of development of tolerance, and frequency and severity of adverse effects exists for epidural or intrathecal therapy with the drug in this population; therefore, initial dosage should be selected carefully based on clinical assessment of response to test doses and consideration of the patient’s age and infirmity on their ability to clear the drug, particularly in those receiving the drug epidurally.

No overall differences in safety and efficacy of morphine sulfate extended-release liposomal injection (DepoDur) (at same or lower doses) in those ≥65 years of age compared with younger adults, but possibility of increased sensitivity in some geriatric individuals cannot be ruled out. Comorbid conditions may predispose geriatric patients to serious adverse events (e.g., respiratory depression, ileus, hypotension, MI). Use with caution in this age group and select dosage at the lower end of the dosage range.

Hepatic Impairment

Use with caution and in reduced dosage in patients with severe hepatic impairment.

Morphine sulfate extended-release liposomal injection (DepoDur) is intended for single-dose administration; accumulation of morphine or its metabolites not expected in patients with hepatic impairment.

Renal Impairment

Use with caution and in reduced dosage in patients with severe renal impairment since accumulation (over several days) of high systemic concentrations may occur in some patients.

Morphine sulfate extended-release liposomal injection (DepoDur) is intended for single-dose administration; accumulation of morphine or its metabolites not expected in patients with renal impairment.

Common Adverse Effects

CNS effects (dizziness, visual disturbances, mental clouding or depression, sedation, coma, euphoria, dysphoria, weakness, faintness, agitation, restlessness, nervousness, seizures, delirium, insomnia) and GI effects (nausea, vomiting, constipation).

Opiate agonists may interfere with evaluation of CNS function, especially relative to consciousness levels, pupillary changes, and respiratory depression, thereby masking the patient’s clinical course.

May increase the risk of water intoxication in postoperative patients because of stimulation of the release of vasopressin.

Drug Interactions

Drugs Associated with Serotonin Syndrome

Risk of serotonin syndrome when used with other serotonergic drugs. May occur at usual dosages. Symptom onset generally occurs within several hours to a few days of concomitant use, but may occur later, particularly after dosage increases. (See Advice to Patients.)

If concomitant use of other serotonergic drugs is warranted, monitor patients for serotonin syndrome, particularly during initiation of therapy and dosage increases.

If serotonin syndrome is suspected, discontinue morphine, other opiate therapy, and/or any concurrently administered serotonergic agents.

Specific Drugs

Morphine Pharmacokinetics

Absorption

Bioavailability

Variably absorbed from the GI tract. Oral bioavailability ≤40%.

Extent of absorption from conventional oral preparations (immediate-release preparations) and extended-release oral preparations is essentially the same, but time to peak plasma concentrations is longer and peak plasma concentrations are lower with extended-release preparations.

Rectal administration: Absorption from rectal suppository is greater than that from the oral solution.

Intrathecal administration: Absorbed slowly into systemic circulation, accounting for the prolonged duration of action by this route.

Epidural administration (morphine sulfate injection): Systemic absorption is rapid, with plasma concentration-time profiles that closely resemble those attained after IV or IM administration.

Epidural administration (morphine sulfate extended-release liposomal injection [DepoDur]): Drug is released from the multivesicular liposomes over time. Systemic AUC is similar to that achieved with epidural administration of morphine sulfate injection, but peak plasma concentrations are lower with the liposomal formulation.

Onset

Oral administration (conventional preparations): Peak analgesia within 60 minutes.

Rectal administration: Peak analgesia 20–60 minutes after administration.

Sub-Q: Peak analgesia within 50–90 minutes and maximal respiratory depression within 90 minutes.

IV injection: Peak analgesia within 20 minutes and maximal respiratory depression within 7 minutes.

IM administration: Peak analgesia within 30–60 minutes and maximal respiratory depression within 30 minutes.

Duration

Following oral, rectal, sub-Q, IM, or IV administration, analgesia may be maintained up to 7 hours.

Sensitivity of the respiratory center returns to normal within 2–3 hours, but minute volume may remain below normal for 4–5 hours.

Food

Conventional preparations: Food may increase extent of GI absorption.

Extended-release capsules: Food may decrease rate of absorption, but extent of absorption does not appear to be affected.

Plasma Concentrations

Extended-release capsule (Avinza): Peak 30 minutes.

Extended-release capsule (Kadian): Peak 8.6–10.3 hours.

Extended-release tablets (MS Contin): Peak 4.4 hours.

Extended-release tablets (Oramorph SR): Peak 3.6–3.8 hours.

Intrathecal or epidural administration (morphine sulfate injection): Peak approximately 5–10 minutes.

Epidural administration (morphine sulfate extended-release liposomal injection [DepoDur]): Peak approximately 1 hour.

Because of the blood-brain barrier, injection of morphine sulfate into peripheral circulation results in systemic plasma concentrations that remain higher than corresponding CNS concentrations.

Distribution

Extent

Distributed into muscle, kidneys, liver, GI tract, lungs, spleen, and brain.

Approximately 4% of an epidurally injected dose distributes into CSF; distribution across the dura is slow, with peak CSF concentrations occurring 60–90 minutes after an epidural dose.

Crosses the placenta. Small amounts distributed into the milk.

Plasma Protein Binding

20–36% bound to plasma proteins; 54% bound to muscle tissue.

Elimination

Metabolism

Metabolized principally in the liver and undergoes conjugation with glucuronic acid.

Secondary conjugation also occurs, which forms a pharmacologically active metabolite.

Plasma concentrations of the active metabolite substantially exceed those of unchanged drug, and the active metabolite appears to contribute substantially to the drug’s pharmacologic activity.

Elimination Route

Excreted in urine mainly as inactive metabolites; up to 2–12% of a dose is eliminated as unchanged drug in urine; 7–10% of a dose is excreted in feces.

Half-life

IV or IM: Mean terminal half-life is 1.5–4.5 hours.

Epidural administration (morphine sulfate injection): Mean terminal plasma half-life is 90 minutes and mean terminal half-life in CSF is about 6 hours.

Epidural administration (morphine sulfate extended-release liposomal injection [DepoDur]): Mean plasma half-life is 16.2–23.9 hours.

Intrathecal administration: Mean terminal half-life in CSF is 90 minutes.

Special Populations

Clearance reduced in patients with hepatic impairment.

Renal impairment: Accumulation of the active metabolite occurs, which can result in enhanced and prolonged opiate activity.

Stability

Storage

When exposed to air, morphine sulfate gradually loses its water of hydration; the drug darkens on prolonged exposure to light.

Oral

Conventional Tablets or Solution

Tight, light-resistant containers at 15–30°C.

Extended-Release Capsules and Tablets

Tight, light-resistant containers at 25°C (may be exposed to 15–30°C).

Parenteral

Injection

15–30°C; protect from light; do not freeze.

Astramorph/PF, Duramorph, and Infumorph injections and injections for use in a compatible patient-controlled infusion device contain no preservatives and are intended for single use only; discard unused portions.

Morphine sulfate extended-release liposomal injection (DepoDur): 2–8°C; do not freeze. May be stored at 15–30°C for ≤30 days in sealed, intact vials. Do not heat sterilize or gas sterilize. Administer dose within 4 hours after withdrawal from the vial; discard unused portions.

Compatibility

Parenteral

Specialized references should be consulted for specific compatibility information.

Solution CompatibilityHID

Drug Compatibility

Actions

• A potent analgesic; shares the actions of the opiate agonists.

• Opiate agonists alter perception of and emotional response to pain.

• Precise mechanism of action has not been fully elucidated; opiate agonists act at several CNS sites, involving several neurotransmitter systems to produce analgesia.

• Pain perception is altered in the spinal cord and higher CNS levels (e.g., substantia gelatinosa, spinal trigeminal nucleus, periaqueductal gray, periventricular gray, medullary raphe nuclei, hypothalamus).

• Opiate agonists do not alter the threshold or responsiveness of afferent nerve endings to noxious stimuli, nor peripheral nerve impulse conduction.

• Opiate agonists act at specific receptor binding sites in the CNS and other tissues; opiate receptors are concentrated in the limbic system, thalamus, striatum, hypothalamus, midbrain, and spinal cord.

• Agonist activity at the opiate μ- or κ-receptor can result in analgesia, miosis, and/or decreased body temperature.

• Agonist activity at the μ-receptor can also result in suppression of opiate withdrawal (and antagonist activity can result in precipitation of withdrawal).

• Respiratory depression may be mediated by μ-receptors, possibly μ₂-receptors (which may be distinct from μ₁-receptors involved in analgesia); κ- and δ-receptors may also be involved in respiratory depression.

Advice to Patients

• Importance of informing patients that morphine may impair mental and/or physical ability required for performance of potentially hazardous tasks; avoid driving or operating heavy machinery until effects on individual are known.

• Risk of respiratory depression following overdosage. Advise patients of the benefits of naloxone following opiate overdose and of their options for obtaining the drug.

• Risk of potentially fatal additive effects (e.g., profound sedation, respiratory depression, coma) if used concomitantly with benzodiazepines or other CNS depressants, including alcohol and other opiates, either therapeutically or illicitly; avoid concomitant use unless such use is supervised by clinician. Importance of informing patients that morphine should not be combined with alcohol.

• Importance of informing patients that this is a drug of potential abuse and should also be protected from theft.

• Importance of informing patients that this medication should never be given to anyone other than the individual for whom it was prescribed.

• Importance of informing patients to keep this and all medications in a secure location and out of the reach of children.

• Importance of informing patients that morphine dosage should not be adjusted without consulting with a clinician.

• Potential risk of serotonin syndrome with concurrent use of morphine and other serotonergic agents. Importance of immediately contacting clinician if manifestations of serotonin syndrome (e.g., agitation, hallucinations, tachycardia, labile BP, fever, excessive sweating, shivering, shaking, muscle stiffness, twitching, loss of coordination, nausea, vomiting, diarrhea) develop.

• Potential risk of adrenal insufficiency. Importance of contacting clinician if manifestations of adrenal insufficiency (e.g., nausea, vomiting, loss of appetite, fatigue, weakness, dizziness, hypotension) develop.

• Possible risk (although causality not established) of hypogonadism or androgen deficiency with long-term opiate agonist or partial agonist use. Importance of informing clinician if decreased libido, impotence, erectile dysfunction, amenorrhea, or infertility occurs.

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses.

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed. Advise women of childbearing potential that prolonged use of opiates during pregnancy may result in neonatal opiate withdrawal syndrome, which can be life-threatening if not recognized and treated.

• Importance of informing patients of other important precautionary information. (See Cautions.)

Morphine Oral Solution

• Importance of providing copy of morphine sulfate oral solutions medication guide. Importance of patients reading the medication guide before initiating therapy and each time the oral solution is dispensed.

• Importance of providing careful instructions on how to measure and administer the prescribed dose. For patients receiving the oral solution containing morphine sulfate 100 mg/5 mL, importance of instructing patient to always use the graduated oral syringe supplied by the manufacturer to ensure that the dose is measured and administered accurately.

• Risk of fatal respiratory depression if the 100-mg/5-mL oral solution is given to patients who are not opiate tolerant.

• Importance of instructing patients receiving prescriptions for morphine sulfate oral solution as to which concentration they have been prescribed; inform patient whenever the concentration is changed.

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Subject to control under the Federal Controlled Substances Act of 1970 as a schedule II (C-II) drug when available as a single entity or as a schedule III (C-III) drug when available as a fixed-combination preparation in a concentration of ≤0.5 mg per mL or g combined with a therapeutic amount of one or more nonopiate drugs.

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