Pharmacology of Substance Use Flashcards

Disulfiram (Antabuse) produces its aversive effect by inhibiting which enzyme?

Answer: Aldehyde dehydrogenase (ALDH)

Disulfiram blocks ALDH, the enzyme that converts acetaldehyde to acetate; acetaldehyde accumulates and causes flushing, nausea, vomiting, and cardiovascular symptoms.

Which cannabinoid receptor subtype mediates most of THC's psychoactive effects?

Answer: CB1 receptors in the central nervous system

THC is a partial agonist at CB1 receptors concentrated in the basal ganglia, hippocampus, cerebellum, and prefrontal cortex, producing its psychoactive, amnestic, and motor effects.

Acamprosate's therapeutic mechanism in alcohol use disorder involves:

Answer: Modulating glutamate and GABA activity to reduce post-acute withdrawal symptoms

Chronic alcohol use upregulates NMDA glutamate receptors; acamprosate reduces glutamate hyperactivity during abstinence and stabilizes GABAergic tone, alleviating protracted withdrawal discomfort.

Phencyclidine (PCP) produces its distinctive dissociative effects primarily by:

Answer: Noncompetitively antagonizing NMDA glutamate receptors

PCP binds within the ion channel of the NMDA receptor and blocks glutamate-mediated transmission, producing analgesia, dissociation, and psychosis-like symptoms.

A client on buprenorphine maintenance presents with acute severe pain after a car accident. The MOST appropriate analgesic strategy is:

Answer: Continue buprenorphine and add non-opioid analgesics plus, if needed, high-dose full agonist opioids

Buprenorphine's high mu-receptor affinity means full agonists must compete, but continuing buprenorphine prevents withdrawal and addiction relapse; multimodal analgesia with high-dose opioids can still provide pain relief.

Inhalant intoxication leading to 'sudden sniffing death' is most commonly caused by:

Answer: Cardiac arrhythmia triggered by catecholamine sensitization of the myocardium

Halogenated hydrocarbons sensitize cardiac tissue to endogenous catecholamines; sudden exertion or fright after inhalation can trigger fatal ventricular fibrillation within minutes.

Which statement about nicotine pharmacology is MOST accurate?

Answer: Nicotine stimulates nicotinic acetylcholine receptors, ultimately increasing mesolimbic dopamine

Nicotine binds neuronal nAChRs on VTA dopamine neurons, stimulating dopamine release in the nucleus accumbens through the same reward pathway as other drugs of abuse.