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Morphine Dosage

Medically reviewed by Drugs.com. Last updated on Aug 26, 2021.

Applies to the following strengths: 15 mg/mL; 10 mg; 15 mg; 30 mg; 2 mg/mL; 4 mg/mL; 8 mg/mL; 10 mg/mL; 10 mg/12 to 24 hr; 20 mg/12 to 24 hr; 30 mg/12 to 24 hr; 40 mg/12 to 24 hr; 50 mg/12 to 24 hr; 60 mg/12 to 24 hr; 80 mg/12 to 24 hr; 100 mg/12 to 24 hr; 200 mg/12 to 24 hr; 200 mg/12 hours; 15 mg/12 hr; 30 mg/12 hr; 60 mg/12 hours; 100 mg/12 hours; 10 mg/5 mL; 20 mg/5 mL; 20 mg/mL; 5 mg; 20 mg; 25 mg/mL; 50 mg/mL; 25 mg/mL preservative-free; 0.5 mg/mL preservative-free; 1 mg/mL preservative-free; 1 mg/mL; 5 mg/mL; 200 mg/200 mL-D5%; 5%-20 mg/100 mL; 30 mg/24 hours; 60 mg/24 hours; 90 mg/24 hours; 120 mg/24 hours; 45 mg/24 hours; 75 mg/24 hours; 15 mg/8 to 12 hr; 30 mg/8 to 12 hr; 60 mg/8 to 12 hr; 100 mg/8 to 12 hr; 200 mg/8 to 12 hr; 100 mg/24 hours; 20 mg/24 hr; 50 mg/24 hours; 10 mg-0.9%/100 mL; 1 mg/mL-NaCl 0.9%; 2 mg/mL-D5%; 0.5 mg/mL; sulfate; 2 mg/mL preservative-free; 4 mg/mL preservative-free; 8 mg/mL preservative-free; 10 mg/mL preservative-free; 15 mg/mL preservative-free; 5 mg/mL preservative-free; 10 mg/0.7 ml; 2 mg/mL-NaCl 0.9%; 4 mg/mL-NaCl 0.9%; 70 mg/12 to 24 hr; 130 mg/12 to 24 hr; 150 mg/12 to 24 hr; 200 mg/24 hours; 10 mg/24 hr; 0.5 mg/mL-NaCl 0.9%; 0.5 mg/mL-NaCl 0.9% preservative-free; 1 mg/mL-NaCl 0.9% preservative-free; 5 mg/mL-NaCl 0.9%; 50 mg/mL preservative-free; 0.4 mg/mL; 4 mg/mL-NaCl 0.9% preservative-free

Usual Adult Dose for Pain

Individualize dosing regimen taking into account severity of pain, response to therapy, prior analgesic treatment experience, and risk factors for addiction, abuse, and misuse:

ORAL:
Immediate-release (IR):
OPIOID-NAIVE and OPIOID NON-TOLERANT:

  • IR tablets: Initial dose: 15 to 30 mg orally every 4 hours as needed to manage pain
  • IR oral solution: Initial dose: 10 to 20 mg orally every 4 hours as needed to manage pain
TITRATION AND MAINTENANCE: Individually titrate to a dose that provides an appropriate balance between pain management and opioid-related adverse reactions
IMPORTANT NOTE: Oral solution is available in 3 concentrations 2 mg/mL, 4 mg/mL, and 20 mg/mL; reserve use of 20 mg/mL concentration for patients who are opioid-tolerant

PARENTERAL:
IV: 0.1 mg to 0.2 mg/kg via slow IV injection every 4 hours as needed to manage pain; alternatively, 2 to 10 mg IV (based on 70 kg adult)
IM: 10 mg IM every 4 hours as needed to manage pain (based on 70 kg adult)
TITRATION AND MAINTENANCE: Individually titrate to a dose that provides an appropriate balance between pain management and opioid-related adverse reactions
IMPORTANT NOTE: IM administration is not the recommended route of administration due to its painful administration, wide fluctuations in muscle absorption, 30 to 60-minute lag to peak effect, and rapid fall off of action compared to oral administration

CONVERSION from Parenteral to Oral Morphine:
  • Between 3 and 6 mg of oral morphine provides pain relief equivalent to 1 mg of parenteral morphine

PATIENT CONTROLLED ANALGESIA (PCA): For use in a compatible infusion device; patient must be closely monitored because of the considerable variability in both dose requirements and patient response. Mean morphine self-administration rate during clinical trials was 1 to 10 mg/hour during clinical trials. The following is provided as guidance; doses should be individualized:
  • Loading dose: 2.5 mg
  • Demand dose: 0.5 to 2 mg
  • Lockout: 10-minute
Maximum Dosing: Opioid Naive: 10 mg/hour; Opioid Tolerant: 30 mg/hour, although greater rates may be needed in select patients

Epidural Administration:
  • Initial dose: 5 mg in the lumbar region may provide satisfactory pain relief for up to 24 hours
  • If adequate pain relief is not achieved within 1-hour, doses of 1 to 2 mg may be given at intervals sufficient to assess effectiveness
Maximum dose: 10 mg per 24 hours

Intrathecal Administration: Dosage is usually one-tenth that of epidural dosage
  • Initial dose: 0.2 to 1 mg may provide satisfactory pain relief for up to 24 hours
  • Repeated intrathecal injections are not recommended
  • A constant intravenous infusion of naloxone 0.6 mg/hr for 24 hours may be used to reduce the incidence of potential side effects

Comments:
  • Monitor closely for respiratory depression, especially within the first 24 to 72 hours of initiating therapy and with all dose increases.
  • Because of the risks of addiction, abuse, and misuse with opioids, reserve use for patients for whom alternative treatment options (e.g., non-opioid analgesics or opioid combination products) are ineffective, not tolerated, or would be otherwise inadequate to provide sufficient management of pain.

Use: For the management of acute pain severe enough to require an opioid analgesic and for which alternative treatments are inadequate.

Usual Adult Dose for Chronic Pain

Individualize dosing regimen taking into account severity of pain, response to therapy, prior analgesic treatment experience, and risk factors for addiction, abuse, and misuse: A single dose greater than 60 mg, a total daily dose greater than 120 mg, and the 20 mg/mL oral solution should be restricted to use in opioid-tolerant patients only:

ORAL:
Immediate-release (IR):
OPIOID-NAIVE and OPIOID NON-TOLERANT:

  • IR tablets: Initial dose: 15 to 30 mg orally every 4 hours
  • IR oral solution: Initial dose: 10 to 20 mg orally every 4 hours
TITRATION AND MAINTENANCE: Individually titrate to a dose that provides an appropriate balance between pain management and opioid-related adverse reactions; when using IR formulations for chronic pain, doses should be scheduled around the clock, or consider switching to an ER formulation

CONVERSION of Immediate-Release to Extended-Release: At a given dose, the same total amount of morphine is available from an IR and ER formulation, however, conversion to an equivalent daily dose of an ER formulation could lead to excessive sedation at peak serum levels; monitor closely for signs of excessive sedation and respiratory depression

Extended-release (ER):
  • ER Tablets (OPIOID-NAIVE and OPIOID NON-TOLERANT): Initial dose: 15 mg orally every 8 or 12 hours
  • ER Capsules (OPIOID NAIVE): Begin treatment with an immediate-release morphine
  • ER Capsules (OPIOID NON-TOLERANT): Initial dose: 30 mg orally every 24 hours
TITRATION AND MAINTENANCE: Adjust dose every 1 to 2 days as needed to obtain an appropriate balance between pain management and opioid-related adverse reactions; for patients experiencing inadequate analgesia with once a day ER capsules or twice a day ER tablets, may consider increasing dose frequency to every 12 hours for ER capsules or every 8 hours for ER tablets; goal should be to find the lowest effective dosage for the shortest duration consistent with individual patient treatment goals

IMPORTANT NOTES:
  • Parenteral to Oral Morphine Ratio: 1 mg parenteral morphine provides analgesia equivalent to between 2 and 6 mg of oral morphine
  • ER formulations are not bioequivalent and therefore, not interchangeable

CONVERSIONS from Other Opioids:
  • Discontinue all other around-the-clock opioid drugs when initiating ER morphine
  • Opioid equivalent tables will be helpful to guide conversion, but it should be understood that wide inter-patient variability in the potency of opioid drugs and formulations is not accounted for in these tables; conversions should be done carefully and with close monitoring for signs and symptoms of opioid withdrawal, over sedation, and toxicity
  • When converting between different opioids or different formulations, it is safer to underestimate the 24-hour dose and provide rescue medication than to overestimate and manage an overdose

SUPPOSITORY:
Usual Adult Dose: 10 to 20 mg rectally every 4 hours
  • Dose should be individualized

Comments:
  • Monitor closely for respiratory depression, especially within the first 24 to 72 hours of initiating therapy and with all dose increases.
  • Use of higher starting doses in patients who are not opioid tolerant may cause fatal respiratory depression with first dose; initial dose selection should take into account degree of opioid tolerance, patient's general condition, medical status, concurrent medications, type and severity of pain, and risk factors for abuse, addiction, or diversion.
  • Opioid tolerant patients are those who have received for 1 week or longer: oral morphine 60 mg/day; transdermal fentanyl 25 mcg/hr; oral oxycodone 30 mg/day; oral hydromorphone 8 mg/day; oral oxymorphone 25 mg/day or an equianalgesic dose of another opioid.
  • Extended-release products are reserved for use in patients for whom alternative treatment options (e.g., non-opioid analgesics or immediate-release opioids) are ineffective, not tolerated, or would be otherwise inadequate to provide sufficient management of pain; these products are not intended to be used as as-needed (prn) analgesics.

Use: For the management of pain severe enough to require daily, around-the-clock, long-term opioid treatment and for which alternative treatment options are inadequate.

NEURAXIAL ADMINISTRATION: Patients must be observed in a fully equipped and staffed environment for at least 24 hours after each test dose and, as appropriate, for the first several days after catheter implantation
  • For Epidural Administration: Initial dose: 3.5 to 7.5 mg/day (opioid non-tolerant) or 4.5 to 10 mg/day (some degree of opioid tolerance); dose requirements may increase significantly during treatment; daily dose limit for each patient must be individualized
  • For use in a compatible infusion device; patient must be closely monitored because of the considerable variability in both dose requirements and patient response. Mean morphine self-administration rate during clinical trials was 1 to 10 mg/hour during clinical trials. The following is provided as guidance; doses should be individualized:
  • Demand dose: 0.5 to 2 mg

Frequently asked questions

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.