Addiction Medicine Certification Pharmacology & Medication Management 2 — Questions and Answers
Question 1: A patient on methadone maintenance therapy develops QTc prolongation >500ms on ECG. What is the most appropriate next step?
- Continue methadone at current dose and recheck ECG in 1 month
- Reduce or discontinue methadone and consider switching to buprenorphine (Correct answer)
- Add a beta-blocker to counteract the QTc prolongation
- Increase the methadone dose to achieve better pain control
Correct answer: Reduce or discontinue methadone and consider switching to buprenorphine
QTc >500ms on methadone carries significant risk of torsades de pointes and warrants dose reduction or transition to buprenorphine, which has a much lower cardiac risk profile.
Question 2: Which benzodiazepine is preferred for alcohol withdrawal management in patients with severe hepatic impairment due to its lack of active metabolites?
- Diazepam
- Chlordiazepoxide
- Lorazepam (Correct answer)
- Clonazepam
Correct answer: Lorazepam
Lorazepam (along with oxazepam and temazepam) undergoes direct glucuronidation without forming active metabolites, making it safer in hepatic impairment.
Question 3: A patient taking buprenorphine/naloxone sublingually reports that the naloxone component is causing them distress. Which statement about naloxone in this formulation is correct?
- Naloxone is well absorbed sublingually and contributes to the therapeutic effect
- Naloxone has poor sublingual bioavailability and is primarily a deterrent to injection misuse (Correct answer)
- Naloxone blocks buprenorphine's effect on mu-opioid receptors when taken sublingually
- Naloxone should be removed from the formulation for patients with opioid sensitivity
Correct answer: Naloxone has poor sublingual bioavailability and is primarily a deterrent to injection misuse
Naloxone has very poor sublingual bioavailability (~3%), so it does not meaningfully block buprenorphine's effects when taken as directed; it is included to precipitate withdrawal if the product is injected.
Question 4: Which medication used in alcohol use disorder works by sensitizing patients to acetaldehyde, causing an aversive reaction when alcohol is consumed?
- Naltrexone
- Acamprosate
- Disulfiram (Correct answer)
- Gabapentin
Correct answer: Disulfiram
Disulfiram inhibits aldehyde dehydrogenase, causing accumulation of acetaldehyde when alcohol is consumed, resulting in flushing, nausea, vomiting, and palpitations.
Question 5: Acamprosate is thought to reduce alcohol cravings primarily through which mechanism?
- Blocking mu-opioid receptors to reduce reward
- Modulating glutamate (NMDA) and GABA activity to reduce neuronal hyperexcitability (Correct answer)
- Inhibiting aldehyde dehydrogenase to cause an aversive reaction
- Stimulating dopamine release in the nucleus accumbens
Correct answer: Modulating glutamate (NMDA) and GABA activity to reduce neuronal hyperexcitability
Acamprosate modulates glutamatergic and GABAergic neurotransmission to reduce the neurological hyperexcitability associated with prolonged abstinence from alcohol.
Question 6: A patient with opioid use disorder wants to start naltrexone (Vivitrol). They last used heroin 5 days ago. Before initiating, you should:
- Start naltrexone immediately since 5 days is sufficient for heroin clearance
- Perform a naloxone challenge test or confirm negative urine opioid screen before dosing (Correct answer)
- Administer a low test dose of naltrexone and observe for 30 minutes
- Wait a full 14 days after last opioid use regardless of the drug used
Correct answer: Perform a naloxone challenge test or confirm negative urine opioid screen before dosing
A naloxone challenge or confirmed negative urine screen is recommended before naltrexone initiation to prevent precipitating severe opioid withdrawal in a physically dependent patient.
Question 7: Which of the following is a contraindication to prescribing buprenorphine for opioid use disorder?
- Current use of an SSRI antidepressant
- Concurrent use of benzodiazepines in a stable patient
- Acute hepatitis with ALT >5x upper limit of normal and rising (Correct answer)
- History of prior opioid overdose
Correct answer: Acute hepatitis with ALT >5x upper limit of normal and rising
Severe or acute hepatic injury (ALT >5x ULN and rising) is a contraindication because buprenorphine is extensively hepatically metabolized and can cause further hepatotoxicity.
Addiction Medicine Certification Pharmacology & Medication Management 2
A patient on methadone maintenance therapy develops QTc prolongation >500ms on ECG.
What is the most appropriate next step?