Morphine conversion reference
Check OpioidCalc's OME factors by route, then open the formulation-specific pharmacology, cautions and supporting sources.
Educational reference for qualified healthcare professionals. Conversion factors estimate oral morphine equivalent daily dose. They are not a recommended switching dose. Confirm the result with a current source and local guidance.
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Current OpioidCalc factors
Multiply the dose or delivery rate in the stated units by the factor to estimate mg oral morphine equivalent per day. These are the factors currently used by OpioidCalc. Methadone uses 4.7 when converting methadone to OME.
| Route | Input units | OME factor |
|---|---|---|
| Oral | mg/day | 1 |
| Parenteral | mg/day | 3 |
Compare a complete regimen in the app
Formulations and cautions
Choose a formulation to read its pharmacology, population, limitations and source references.
OralDefault in appImmediate-release tablet
App source review: 27 August 2026
View details and sources
Immediate-release tablet
App source review: 27 August 2026
View details and sources- Peak concentration or effect
- Maximum analgesic effect at approximately 60 minutes
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate immediate-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 30 July 2026. App review 27 August 2026. Regulatory product information.
- Steady state
- Within 48 hours when administered every six hours
Population: Adults described in the cited product information
Applicability: United States
- Limitation: The cited regimen describes study conditions, not a dosing recommendation.
- Morphine sulfate immediate-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 30 July 2026. App review 27 August 2026. Regulatory product information.
- Bioavailability
- Less than 40%, with large interindividual variability
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate immediate-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 30 July 2026. App review 27 August 2026. Regulatory product information.
- Receptor activity
- Full mu-opioid receptor agonist.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate immediate-release tablet prescribing information12.1 Mechanism of Action. United States. Source revised 30 July 2026. App review 27 August 2026. Regulatory product information.
- Metabolism
- Hepatic glucuronidation forms morphine-3-glucuronide and morphine-6-glucuronide.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate immediate-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 30 July 2026. App review 27 August 2026. Regulatory product information.
- Active metabolites
- Morphine-6-glucuronide is analgesically active; morphine-3-glucuronide is not analgesic.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate immediate-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 30 July 2026. App review 27 August 2026. Regulatory product information.
- Elimination
- Glucuronides are eliminated primarily in urine; about 10% is excreted unchanged.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate immediate-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 30 July 2026. App review 27 August 2026. Regulatory product information.
- Renal impairment
- Morphine glucuronides can accumulate markedly in renal failure.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate immediate-release tablet prescribing information8.7 Renal Impairment. United States. Source revised 30 July 2026. App review 27 August 2026. Regulatory product information.
- Hepatic impairment
- Cirrhosis reduces clearance and increases half-life.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate immediate-release tablet prescribing information8.6 Hepatic Impairment. United States. Source revised 30 July 2026. App review 27 August 2026. Regulatory product information.
OralImmediate-release oral solution
App source review: 27 August 2026
View details and sources
Immediate-release oral solution
App source review: 27 August 2026
View details and sources- Peak concentration or effect
- Maximum analgesic effect at approximately 60 minutes
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate oral solution prescribing information12.3 Pharmacokinetics. United States. Source revised 28 July 2026. App review 27 August 2026. Regulatory product information.
- Steady state
- Within 48 hours when administered every six hours
Population: Adults described in the cited product information
Applicability: United States
- Limitation: The cited regimen describes study conditions, not a dosing recommendation.
- Morphine sulfate oral solution prescribing information12.3 Pharmacokinetics. United States. Source revised 28 July 2026. App review 27 August 2026. Regulatory product information.
- Bioavailability
- Less than 40%, with large interindividual variability
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate oral solution prescribing information12.3 Pharmacokinetics. United States. Source revised 28 July 2026. App review 27 August 2026. Regulatory product information.
- Receptor activity
- Full mu-opioid receptor agonist.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate oral solution prescribing information12.1 Mechanism of Action. United States. Source revised 28 July 2026. App review 27 August 2026. Regulatory product information.
- Metabolism
- Hepatic glucuronidation forms morphine-3-glucuronide and morphine-6-glucuronide.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate oral solution prescribing information12.3 Pharmacokinetics. United States. Source revised 28 July 2026. App review 27 August 2026. Regulatory product information.
- Active metabolites
- Morphine-6-glucuronide is analgesically active; morphine-3-glucuronide is not analgesic.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate oral solution prescribing information12.3 Pharmacokinetics. United States. Source revised 28 July 2026. App review 27 August 2026. Regulatory product information.
- Elimination
- Glucuronides are eliminated primarily in urine; about 10% is excreted unchanged.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate oral solution prescribing information12.3 Pharmacokinetics. United States. Source revised 28 July 2026. App review 27 August 2026. Regulatory product information.
- Renal impairment
- Morphine glucuronides can accumulate markedly in renal failure.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate oral solution prescribing information8.7 Renal Impairment. United States. Source revised 28 July 2026. App review 27 August 2026. Regulatory product information.
- Hepatic impairment
- Cirrhosis reduces clearance and increases half-life.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate oral solution prescribing information8.6 Hepatic Impairment. United States. Source revised 28 July 2026. App review 27 August 2026. Regulatory product information.
OralModified-release tablet
App source review: 27 August 2026
View details and sources
Modified-release tablet
App source review: 27 August 2026
View details and sources- Steady state
- About 1 day
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- MS CONTIN extended-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 14 August 2026. App review 27 August 2026. Regulatory product information.
- Bioavailability
- Approximately 20% to 40%
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- MS CONTIN extended-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 14 August 2026. App review 27 August 2026. Regulatory product information.
- Formulation behaviour
- Slower release than immediate-release morphine; authorised for every-8- or every-12-hour administration.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: The dosing interval is not presented as a precise clinical duration.
- MS CONTIN extended-release tablet prescribing information2.3 and 12.3. United States. Source revised 14 August 2026. App review 27 August 2026. Regulatory product information.
- Receptor activity
- Full mu-opioid receptor agonist.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- MS CONTIN extended-release tablet prescribing information12.1 Mechanism of Action. United States. Source revised 14 August 2026. App review 27 August 2026. Regulatory product information.
- Metabolism
- Hepatic glucuronidation forms morphine-3-glucuronide and morphine-6-glucuronide.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- MS CONTIN extended-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 14 August 2026. App review 27 August 2026. Regulatory product information.
- Active metabolites
- Morphine-6-glucuronide is analgesically active; morphine-3-glucuronide is not analgesic.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- MS CONTIN extended-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 14 August 2026. App review 27 August 2026. Regulatory product information.
- Elimination
- Glucuronides are eliminated primarily in urine; about 10% is excreted unchanged.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- MS CONTIN extended-release tablet prescribing information12.3 Pharmacokinetics. United States. Source revised 14 August 2026. App review 27 August 2026. Regulatory product information.
- Renal impairment
- Morphine glucuronides can accumulate markedly in renal failure.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- MS CONTIN extended-release tablet prescribing information8.7 Renal Impairment. United States. Source revised 14 August 2026. App review 27 August 2026. Regulatory product information.
- Hepatic impairment
- Cirrhosis reduces clearance and increases half-life.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- MS CONTIN extended-release tablet prescribing information8.6 Hepatic Impairment. United States. Source revised 14 August 2026. App review 27 August 2026. Regulatory product information.
OralOnce-daily biphasic modified-release capsule
App source review: 27 August 2026
View details and sources
Once-daily biphasic modified-release capsule
App source review: 27 August 2026
View details and sources- Onset
- Plasma morphine was detectable within 30 minutes
Population: Adults described in the cited product information
Applicability: United States
- Limitation: This is concentration evidence, not proven analgesic onset.
- Morphine sulfate biphasic extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Duration
- Concentrations were maintained over the 24-hour interval
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Concentration persistence is not identical to clinical effect duration.
- Morphine sulfate biphasic extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Elimination half-life
- Approximately 24 hours after a single capsule
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate biphasic extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Steady state
- 2 to 3 days
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate biphasic extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Bioavailability
- Less than 40%
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate biphasic extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Formulation behaviour
- Distinct immediate- and extended-release components support once-daily use; food may delay initial concentrations by about one hour.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate biphasic extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Receptor activity
- Full mu-opioid receptor agonist.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate biphasic extended-release capsule prescribing information12.1 Mechanism of Action. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Metabolism
- Hepatic glucuronidation forms morphine-3-glucuronide and morphine-6-glucuronide.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate biphasic extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Active metabolites
- Morphine-6-glucuronide is analgesically active; morphine-3-glucuronide is not analgesic.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate biphasic extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Elimination
- Glucuronides are eliminated primarily in urine; about 10% is excreted unchanged.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate biphasic extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Renal impairment
- Morphine glucuronides can accumulate markedly in renal failure.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate biphasic extended-release capsule prescribing information8.7 Renal Impairment. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
- Hepatic impairment
- Cirrhosis reduces clearance and increases half-life.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate biphasic extended-release capsule prescribing information8.6 Hepatic Impairment. United States. Source revised 1 March 2026. App review 27 August 2026. Regulatory product information.
OralPolymer-coated pellet modified-release capsule
App source review: 27 August 2026
View details and sources
Polymer-coated pellet modified-release capsule
App source review: 27 August 2026
View details and sources- Peak concentration or effect
- Single-dose median 8.6 hours; once-daily steady-state median 10.3 hours
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
- Elimination half-life
- Approximately 11 to 13 hours
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
- Steady state
- Approximately 2 days in the cited cancer-pain study
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
- Bioavailability
- Approximately 20% to 40%
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
- Formulation behaviour
- Polymer-coated pellets produce slower absorption and lower peaks than comparator solution or tablet regimens.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
- Receptor activity
- Full mu-opioid receptor agonist.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information12.1 Mechanism of Action. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
- Metabolism
- Hepatic glucuronidation forms morphine-3-glucuronide and morphine-6-glucuronide.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
- Active metabolites
- Morphine-6-glucuronide is analgesically active; morphine-3-glucuronide is not analgesic.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
- Elimination
- Glucuronides are eliminated primarily in urine; about 10% is excreted unchanged.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information12.3 Pharmacokinetics. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
- Renal impairment
- Morphine glucuronides can accumulate markedly in renal failure.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information8.7 Renal Impairment. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
- Hepatic impairment
- Cirrhosis reduces clearance and increases half-life.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing information8.6 Hepatic Impairment. United States. Source revised 28 November 2025. App review 27 August 2026. Regulatory product information.
ParenteralDefault in appIntramuscular injection
App source review: 27 August 2026
View details and sources
Intramuscular injection
App source review: 27 August 2026
View details and sources- Onset
- 5 to 20 minutes
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate injection prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2025. App review 27 August 2026. Regulatory product information.
- Peak concentration or effect
- Peak analgesia at approximately 60 minutes
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate injection prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2025. App review 27 August 2026. Regulatory product information.
- Duration
- 3 to 4 hours
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate injection prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2025. App review 27 August 2026. Regulatory product information.
- Elimination half-life
- Terminal half-life 1.5 to 4.5 hours
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate injection prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2025. App review 27 August 2026. Regulatory product information.
- Receptor activity
- Full mu-opioid receptor agonist.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate injection prescribing information12.1 Mechanism of Action. United States. Source revised 1 March 2025. App review 27 August 2026. Regulatory product information.
- Metabolism
- Glucuronidation forms morphine-3-glucuronide and morphine-6-glucuronide.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate injection prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2025. App review 27 August 2026. Regulatory product information.
- Active metabolites
- Morphine-6-glucuronide is analgesically active; morphine-3-glucuronide is not analgesic.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate injection prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2025. App review 27 August 2026. Regulatory product information.
- Elimination
- Morphine and glucuronides are eliminated mainly in urine.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate injection prescribing information12.3 Pharmacokinetics. United States. Source revised 1 March 2025. App review 27 August 2026. Regulatory product information.
- Renal impairment
- Active and inactive glucuronides can accumulate in renal impairment.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Morphine sulfate injection prescribing information8.7 Renal Impairment. United States. Source revised 1 March 2025. App review 27 August 2026. Regulatory product information.
ParenteralIntravenous injection
App source review: 27 August 2026
View details and sources
Intravenous injection
App source review: 27 August 2026
View details and sourcesParenteralSubcutaneous injection
App source review: 27 August 2026
View details and sources
Subcutaneous injection
App source review: 27 August 2026
View details and sourcesParenteralContinuous parenteral infusion
App source review: 27 August 2026
View details and sources
Continuous parenteral infusion
App source review: 27 August 2026
View details and sourcesSources used on this page
- Morphine sulfate immediate-release tablet prescribing informationUnited States. Revision date 30 July 2026.
- Morphine sulfate oral solution prescribing informationUnited States. Revision date 28 July 2026.
- MS CONTIN extended-release tablet prescribing informationUnited States. Revision date 14 August 2026.
- Morphine sulfate biphasic extended-release capsule prescribing informationUnited States. Revision date 1 March 2026.
- Morphine sulfate polymer-coated pellet extended-release capsule prescribing informationUnited States. Revision date 28 November 2025.
- Morphine sulfate injection prescribing informationUnited States. Revision date 1 March 2025.
Other medicine references
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