Pharmacology of Substance Use Flashcards

A client maintained on buprenorphine/naloxone reports that injecting the film produces little effect. This is because:

Answer: Naloxone becomes active parenterally and precipitates withdrawal

Naloxone has negligible sublingual bioavailability but is highly active intravenously, so injecting the combination product precipitates opioid withdrawal in dependent users.

MDMA's acute toxicity most commonly causes death through which mechanism?

Answer: Hyperthermia, rhabdomyolysis, and multi-organ failure

MDMA causes serotonin-mediated hyperthermia that, compounded by physical exertion and dehydration, leads to muscle breakdown, renal failure, and death.

Which characteristic of gamma-hydroxybutyrate (GHB) makes it particularly dangerous when combined with alcohol?

Answer: Both substances are CNS depressants with synergistic effects at GABA receptors

GHB and alcohol both potentiate GABA-mediated inhibition; combined use produces synergistic CNS and respiratory depression, dramatically narrowing the margin between intoxication and fatal overdose.

Regarding methamphetamine neurotoxicity, long-term use is most associated with damage to:

Answer: Dopaminergic and serotonergic terminals in the striatum and prefrontal cortex

Methamphetamine causes oxidative stress and excitotoxicity that selectively destroy dopamine and serotonin nerve terminals, contributing to lasting cognitive and mood deficits.

The concept of 'set and setting' is most directly relevant to which substance's variable psychological effects?

Answer: LSD (lysergic acid diethylamide)

Psychedelic experiences with LSD and similar hallucinogens are heavily shaped by the user's mindset and the physical/social environment, a relationship first articulated by Timothy Leary and later validated empirically.

Tolerance to opioids develops most rapidly for which effect?

Answer: Analgesia and euphoria

Analgesic and euphoric effects undergo rapid tolerance through receptor downregulation and desensitization, while constipation and miosis show minimal tolerance even with prolonged use.

A urine drug screen using immunoassay is MOST likely to produce a false positive for opioids in a client who reports taking:

Answer: Poppy seed-containing food

Poppy seeds contain morphine and codeine; ingestion can produce urine morphine concentrations exceeding the standard 300 ng/mL cutoff used in many immunoassay screens.