ADM Pharmacotherapy & Medication-Assisted Treatment 2 — Questions and Answers
Question 1: A patient on buprenorphine/naloxone reports severe pain after a traumatic injury. Which analgesic strategy is most appropriate?
- Discontinue buprenorphine and start full-agonist opioids
- Continue buprenorphine and add non-opioid analgesics plus titrate buprenorphine dose upward if needed (Correct answer)
- Switch to methadone for dual pain and OUD management
- Add low-dose naltrexone for opioid-sparing effect
Correct answer: Continue buprenorphine and add non-opioid analgesics plus titrate buprenorphine dose upward if needed
Buprenorphine should generally be continued and non-opioid multimodal analgesia added; buprenorphine itself provides partial analgesia and abrupt discontinuation risks relapse.
Question 2: Which pharmacokinetic property makes once-monthly injectable buprenorphine (Sublocade) advantageous over daily sublingual formulations?
- Faster onset of action reducing withdrawal symptoms sooner
- Elimination of peak-and-trough plasma fluctuations (Correct answer)
- Higher bioavailability resulting in lower total dose requirements
- Renal excretion allows dose adjustment in hepatic impairment
Correct answer: Elimination of peak-and-trough plasma fluctuations
The subcutaneous depot provides sustained, steady plasma levels, eliminating the peaks and troughs associated with daily sublingual dosing.
Question 3: A patient maintained on methadone 100 mg/day is started on rifampin for tuberculosis. The expected pharmacokinetic interaction is:
- Rifampin inhibits CYP3A4, increasing methadone levels and risk of overdose
- Rifampin induces CYP3A4, markedly decreasing methadone levels and precipitating withdrawal (Correct answer)
- Rifampin competitively binds mu-opioid receptors, reducing methadone efficacy
- Rifampin increases methadone protein binding, reducing free drug availability
Correct answer: Rifampin induces CYP3A4, markedly decreasing methadone levels and precipitating withdrawal
Rifampin is a potent CYP3A4 inducer that accelerates methadone metabolism, often requiring a 50–100% dose increase to prevent withdrawal.
Question 4: Naltrexone extended-release injectable (XR-NTX) is contraindicated within how many days of last opioid use to avoid precipitated withdrawal?
- 3–5 days
- 7–10 days (Correct answer)
- 14–21 days
- 30 days
Correct answer: 7–10 days
A minimum 7–10 day opioid-free period is required before initiating XR-NTX to avoid precipitated withdrawal from opioid receptor blockade.
Question 5: Which statement about acamprosate's mechanism of action in alcohol use disorder is correct?
- It inhibits aldehyde dehydrogenase, causing aversive acetaldehyde accumulation
- It modulates GABA-A receptors and inhibits NMDA receptors to reduce glutamatergic hyperactivity (Correct answer)
- It blocks mu-opioid receptors to reduce alcohol-induced reward
- It increases dopamine reuptake in the nucleus accumbens
Correct answer: It modulates GABA-A receptors and inhibits NMDA receptors to reduce glutamatergic hyperactivity
Acamprosate is thought to restore balance between inhibitory GABA and excitatory glutamate (NMDA) systems dysregulated by chronic alcohol exposure.
Question 6: A woman with OUD is 28 weeks pregnant and using heroin daily. She has no prior MAT. Which is the recommended first-line approach?
- Inpatient medically supervised withdrawal followed by naltrexone
- Initiation of methadone or buprenorphine maintenance therapy (Correct answer)
- Clonidine taper as monotherapy to minimize fetal exposure
- Watchful waiting until delivery, then initiate MAT postpartum
Correct answer: Initiation of methadone or buprenorphine maintenance therapy
Methadone and buprenorphine are the evidence-based standard of care for OUD in pregnancy; opioid withdrawal in pregnancy is associated with fetal distress and preterm labor.
Question 7: Which medication used for alcohol use disorder requires a disulfiram-alcohol reaction test before prescribing to confirm the mechanism?
- Acamprosate
- Naltrexone
- Disulfiram (Correct answer)
- Gabapentin
Correct answer: Disulfiram
Disulfiram inhibits aldehyde dehydrogenase, causing acetaldehyde accumulation when alcohol is consumed, producing flushing, nausea, and cardiovascular symptoms as a deterrent.
ADM Pharmacotherapy & Medication-Assisted Treatment 2
A patient on buprenorphine/naloxone reports severe pain after a traumatic injury.
Which analgesic strategy is most appropriate?