Buprenorphine 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 |
|---|---|---|
| Sublingual | mcg/day | 0.04 |
| Transdermal | mcg/hr | 2.2 |
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Formulations and cautions
Choose a formulation to read its pharmacology, population, limitations and source references.
SublingualDefault in appLow-dose analgesic sublingual tablet
App source review: 27 August 2026
View details and sources
Low-dose analgesic sublingual tablet
App source review: 27 August 2026
View details and sources- Onset
- Approximately 30 minutes
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Tephine 200 microgram sublingual tablet SmPC5.1 Pharmacodynamic properties. United Kingdom. Source revised 22 November 2024. App review 27 August 2026. Regulatory product information.
- Peak concentration or effect
- Peak analgesic effect 60 to 120 minutes
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Tephine 200 microgram sublingual tablet SmPC5.1 Pharmacodynamic properties. United Kingdom. Source revised 22 November 2024. App review 27 August 2026. Regulatory product information.
- Duration
- 6 to 8 hours
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Tephine 200 microgram sublingual tablet SmPC5.1 Pharmacodynamic properties. United Kingdom. Source revised 22 November 2024. App review 27 August 2026. Regulatory product information.
- Elimination half-life
- Approximately 3 hours in this low-dose analgesic tablet label
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Other buprenorphine products report different terminal half-lives; do not generalise across formulations.
- Tephine 200 microgram sublingual tablet SmPC5.2 Pharmacokinetic properties. United Kingdom. Source revised 22 November 2024. App review 27 August 2026. Regulatory product information.
- Receptor activity
- Partial mu-opioid receptor agonist.
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Tephine 200 microgram sublingual tablet SmPC5.1 Pharmacodynamic properties. United Kingdom. Source revised 22 November 2024. App review 27 August 2026. Regulatory product information.
- Metabolism
- N-dealkylation and glucuronidation form norbuprenorphine and conjugates.
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Tephine 200 microgram sublingual tablet SmPC5.2 Pharmacokinetic properties. United Kingdom. Source revised 22 November 2024. App review 27 August 2026. Regulatory product information.
- Active metabolites
- Norbuprenorphine has opioid activity, but clinical contribution after low-dose sublingual use is uncertain.
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Tephine 200 microgram sublingual tablet SmPC5.2 Pharmacokinetic properties. United Kingdom. Source revised 22 November 2024. App review 27 August 2026. Regulatory product information.
- Elimination
- Predominantly faecal elimination; about 27% is recovered in urine.
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- Tephine 200 microgram sublingual tablet SmPC5.2 Pharmacokinetic properties. United Kingdom. Source revised 22 November 2024. App review 27 August 2026. Regulatory product information.
- Formulation behaviour
- The tablet typically dissolves in 5 to 10 minutes.
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Low-dose analgesic tablet only; do not apply to high-dose opioid-dependence tablets or films.
- Tephine 200 microgram sublingual tablet SmPC4.2 Posology. United Kingdom. Source revised 22 November 2024. App review 27 August 2026. Regulatory product information.
TransdermalDefault in app7-day transdermal patch
App source review: 27 August 2026
View details and sources
7-day transdermal patch
App source review: 27 August 2026
View details and sources- Onset
- Quantifiable systemic concentrations at a median of approximately 17 hours
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Quantifiable concentration is not identical to analgesic onset.
- BUTRANS transdermal system prescribing information12.3 Pharmacokinetics. United States. Source revised 1 May 2026. App review 27 August 2026. Regulatory product information.
- Steady state
- By day 3
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- BUTRANS transdermal system prescribing information12.3 Pharmacokinetics. United States. Source revised 1 May 2026. App review 27 August 2026. Regulatory product information.
- Offset after stopping
- After removal, concentrations fall about 50% within 12 hours (range 10 to 24 hours), followed by slower decline.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- BUTRANS transdermal system prescribing information12.3 Pharmacokinetics. United States. Source revised 1 May 2026. App review 27 August 2026. Regulatory product information.
- Elimination half-life
- Apparent terminal half-life approximately 26 hours after patch removal
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- BUTRANS transdermal system prescribing information12.3 Pharmacokinetics. United States. Source revised 1 May 2026. App review 27 August 2026. Regulatory product information.
- Bioavailability
- Approximately 15%
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- BUTRANS transdermal system prescribing information12.3 Pharmacokinetics. United States. Source revised 1 May 2026. App review 27 August 2026. Regulatory product information.
- Receptor activity
- Partial 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.
- BUTRANS transdermal system prescribing information12.1 Mechanism of Action. United States. Source revised 1 May 2026. App review 27 August 2026. Regulatory product information.
- Metabolism
- CYP3A4 N-dealkylation and UGT glucuronidation form norbuprenorphine and conjugates.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- BUTRANS transdermal system prescribing information12.3 Pharmacokinetics. United States. Source revised 1 May 2026. App review 27 August 2026. Regulatory product information.
- Active metabolites
- Norbuprenorphine is pharmacologically active.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Product-specific evidence; do not transfer to other formulations.
- BUTRANS transdermal system prescribing information12.3 Pharmacokinetics. United States. Source revised 1 May 2026. App review 27 August 2026. Regulatory product information.
- Formulation behaviour
- Skin forms a depot; external heat increased exposure and peak concentration in the cited study.
Population: Adults described in the cited product information
Applicability: United States
- Limitation: Heat effects are product- and study-specific; follow the product warning.
- BUTRANS transdermal system prescribing information5.3 and 12.3. United States. Source revised 1 May 2026. App review 27 August 2026. Regulatory product information.
Transdermal96-hour transdermal patch
App source review: 27 August 2026
View details and sources
96-hour transdermal patch
App source review: 27 August 2026
View details and sources- Onset
- Plasma threshold is reached in approximately 12 to 24 hours
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Plasma threshold is not identical to analgesic onset.
- TRANSTEC transdermal patch SmPC5.2 Pharmacokinetic properties. United Kingdom. Source revised 2 February 2026. App review 27 August 2026. Regulatory product information.
- Peak concentration or effect
- Plasma peak at approximately 60 to 80 hours
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- TRANSTEC transdermal patch SmPC5.2 Pharmacokinetic properties. United Kingdom. Source revised 2 February 2026. App review 27 August 2026. Regulatory product information.
- Elimination half-life
- Approximately 30 hours after removal; range 22 to 36 hours
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- TRANSTEC transdermal patch SmPC5.2 Pharmacokinetic properties. United Kingdom. Source revised 2 February 2026. App review 27 August 2026. Regulatory product information.
- Offset after stopping
- Concentrations decline slowly after removal because of continued absorption from the skin depot.
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- TRANSTEC transdermal patch SmPC5.2 Pharmacokinetic properties. United Kingdom. Source revised 2 February 2026. App review 27 August 2026. Regulatory product information.
- Receptor activity
- Partial mu-opioid receptor agonist.
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- TRANSTEC transdermal patch SmPC5.1 Pharmacodynamic properties. United Kingdom. Source revised 2 February 2026. App review 27 August 2026. Regulatory product information.
- Metabolism
- N-dealkylation and glucuronidation form norbuprenorphine and conjugates.
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Product-specific evidence; do not transfer to other formulations.
- TRANSTEC transdermal patch SmPC5.2 Pharmacokinetic properties. United Kingdom. Source revised 2 February 2026. App review 27 August 2026. Regulatory product information.
- Formulation behaviour
- 96-hour patch technology; treatment effect should not be assessed before 24 hours.
Population: Adults described in the cited product information
Applicability: United Kingdom
- Limitation: Do not substitute 7-day BUTRANS pharmacokinetics.
- TRANSTEC transdermal patch SmPC4.2 and 5.2. United Kingdom. Source revised 2 February 2026. App review 27 August 2026. Regulatory product information.
Sources used on this page
Other medicine references
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