Mechanism of action: Buprenorphine balliculeVisual mnemonic: Buprenorphine mascot “Bumper orphan’s Sub in Texas” pinpoint pupils → opioid SubuTEXAS flag SUBmarine periscope on bumper car
What it isPartial mu agonist with high receptor affinity; opioid use disorder and chronic pain.
Why this oneOUD maintenance of choice: safer than methadone, office-prescribable, comparably effective at adequate doses.
What limits itThat same affinity precipitates withdrawal if given too early after a full agonist. Sublingual absorption; QT prolongation at higher doses.
Pearls
Schedule III; no X-waiver needed for office prescribing
Usual target 16 mg/day; some need 24 mg
Monthly SC depots (Brixadi, Sublocade) curb nonadherence and diversion; REMS only
Recommended OUD maintenance in pregnancy and breastfeeding, as is methadone
Opioid dependence — induction (mono product preferred for induction; buprenorphine/naloxone preferred for maintenance)
Adults
Day 1: up to 8 mg SL QD (in 2–4 mg increments); Day 2: 16 mg SL QD
16 mg SL QD; maintenance range 4–24 mg QD
24 mg QD (higher doses not studied in RCTs)
Renal Undefined
Hepatic Severe impairment: consider halving starting and titration incremental doses; monitor for toxicity/overdose
NOT for use as an analgesic — deaths reported in opioid-naïve individuals given a 2 mg SL dose.
Instructions
Administer sublingually as a single daily dose; tablets must be taken whole — do not cut, chew, or swallow.
Place under the tongue until dissolved; no food or drink until fully dissolved; then sip water, swish gently, swallow; wait ≥1 hour before brushing teeth.
Induct only when objective, clear signs of moderate opioid withdrawal are evident — ≥4 h after last short-acting opioid; generally ≥24 h after methadone/long-acting opioids.
Adjust maintenance dose in 2 mg or 4 mg increments/decrements to suppress withdrawal and hold patient in treatment.
Taper gradually when discontinuing to avoid withdrawal.
Strongly consider prescribing an opioid overdose reversal agent (naloxone/nalmefene) at initiation and renewal.
Available strengths
SL tab 2, 8 mg
Cautions
Addiction, abuse, and misuse (Schedule III) — monitor for diversion; limit early refills.
Life-threatening respiratory and CNS depression, especially with benzodiazepines, other CNS depressants, or alcohol.
Unintentional pediatric exposure can be fatal — store out of sight and reach of children.
Neonatal opioid withdrawal syndrome with prolonged use in pregnancy.
Adrenal insufficiency — treat with physiologic corticosteroids and wean off opioid if diagnosed.
Opioid withdrawal with abrupt discontinuation.
Hepatitis/hepatic events — monitor LFTs before and during treatment.
Precipitated opioid withdrawal if taken before agonist effects of other opioids have subsided (or with parenteral misuse).
Overdose risk in opioid-naïve patients; orthostatic hypotension; elevated CSF and intracholedochal pressure; dental problems with sublingual route.
Withdrawal signs and symptoms, insomnia, pain, peripheral edema
Pregnancy Limited data do not indicate increased risk of major malformations; neonatal opioid withdrawal syndrome expected with prolonged use; dose adjustment (often higher) may be needed during pregnancy.
Lactation Present in low levels in human milk (<1% of maternal dose); no adverse reactions shown in breastfed infants — monitor infant for drowsiness and breathing difficulty.
This drug is routinely called serotonergic. By Gillman’s human-effect criteria it does not raise serotonin in the synapse.
Opioid effects and respiratory/CNS-depressant interactions remain important, but this drug is not a clinically significant SRI by the Gillman framework.
Gillman’s four human testsA measurable SERT affinity that fails all four is not clinical serotonicity.