MAC Pharmacology of Substances 3 — Questions and Answers
Question 1: Acamprosate (Campral) reduces alcohol craving primarily by modulating:
- Dopamine D2 receptors in the striatum
- GABA and glutamate (NMDA) receptor balance (Correct answer)
- Serotonin transporter activity
- Mu-opioid receptors in the limbic system
Correct answer: GABA and glutamate (NMDA) receptor balance
Acamprosate restores the disrupted balance between GABA inhibition and glutamate excitation that occurs during protracted alcohol withdrawal.
Question 2: Which opioid is MOST appropriate for a client with severe renal impairment who requires analgesia and is in OUD recovery?
- Codeine, because it is a prodrug with minimal direct renal effects
- Morphine, because it has the longest history of use
- Methadone, used cautiously due to less active metabolite accumulation (Correct answer)
- Hydromorphone, because it is the strongest available
Correct answer: Methadone, used cautiously due to less active metabolite accumulation
Methadone is often preferred in renal impairment because it has no active metabolites that accumulate; morphine and codeine have renally-cleared active metabolites that can cause toxicity.
Question 3: The 'kindling' phenomenon in alcohol use disorder refers to:
- Increasing alcohol tolerance with repeated use
- Each successive withdrawal episode causing more severe symptoms with lower alcohol intake (Correct answer)
- Enhanced euphoria from alcohol over time
- Progressive liver damage independent of withdrawal
Correct answer: Each successive withdrawal episode causing more severe symptoms with lower alcohol intake
Kindling describes how repeated cycles of alcohol withdrawal cause neuronal sensitization, making subsequent withdrawals progressively more severe and seizure-prone.
Question 4: Disulfiram (Antabuse) produces an aversive reaction to alcohol by inhibiting which enzyme?
- Alcohol dehydrogenase (ADH)
- Aldehyde dehydrogenase (ALDH), causing acetaldehyde accumulation (Correct answer)
- Cytochrome P450 2E1 (CYP2E1)
- Monoamine oxidase (MAO)
Correct answer: Aldehyde dehydrogenase (ALDH), causing acetaldehyde accumulation
Disulfiram inhibits ALDH, causing toxic acetaldehyde to accumulate after alcohol ingestion, producing flushing, nausea, and cardiovascular symptoms.
Question 5: A client on buprenorphine/naloxone (Suboxone) asks why injecting it would be less rewarding than injecting heroin. The counselor explains that this is because:
- Naloxone is fully absorbed orally and blocks receptors before buprenorphine
- Naloxone becomes bioavailable intravenously and precipitates withdrawal by blocking opioid receptors (Correct answer)
- Buprenorphine has no ceiling effect when injected
- Suboxone contains an aversive dye that causes vomiting
Correct answer: Naloxone becomes bioavailable intravenously and precipitates withdrawal by blocking opioid receptors
When injected, naloxone becomes systemically active and competitively antagonizes opioid receptors, precipitating acute withdrawal in opioid-dependent individuals.
Question 6: Stimulant-induced psychosis most closely resembles which psychiatric condition?
- Major depressive disorder with psychotic features
- Paranoid schizophrenia (Correct answer)
- Bipolar disorder type I manic episode
- Dissociative identity disorder
Correct answer: Paranoid schizophrenia
Stimulant-induced psychosis, characterized by paranoia, auditory hallucinations, and thought disorganization, closely mimics paranoid schizophrenia due to excess dopaminergic activity.
Question 7: Which benzodiazepine is MOST often recommended for alcohol detoxification because of its long half-life and self-tapering properties?
- Lorazepam (Ativan)
- Oxazepam (Serax)
- Chlordiazepoxide (Librium) or diazepam (Valium) (Correct answer)
- Triazolam (Halcion)
Correct answer: Chlordiazepoxide (Librium) or diazepam (Valium)
Long-acting benzodiazepines like chlordiazepoxide and diazepam are preferred for alcohol detox because they provide a smoother, self-tapering withdrawal due to their long half-lives and active metabolites.
MAC Pharmacology of Substances 3
Acamprosate (Campral) reduces alcohol craving primarily by modulating: