MAC Pharmacology of Substances 4 — Questions and Answers
Question 1: MDMA (ecstasy) primarily exerts its psychoactive effects by causing massive release and reuptake inhibition of:
- Dopamine and norepinephrine only
- Serotonin primarily, with dopamine and norepinephrine also affected (Correct answer)
- GABA and glycine
- Endogenous opioids exclusively
Correct answer: Serotonin primarily, with dopamine and norepinephrine also affected
MDMA primarily causes a massive release of serotonin (5-HT), along with dopamine and norepinephrine, which accounts for its empathogenic, stimulant, and hallucinogenic properties.
Question 2: A client reports using inhalants regularly. The counselor should be most concerned about which acute life-threatening complication?
- Respiratory depression from CNS sedation
- Sudden Sniffing Death Syndrome due to cardiac arrhythmia (Correct answer)
- Hypertensive crisis from norepinephrine surge
- Serotonin syndrome from 5-HT release
Correct answer: Sudden Sniffing Death Syndrome due to cardiac arrhythmia
Sudden Sniffing Death Syndrome can occur even on a first use of inhalants, when catecholamine surge sensitizes the heart to arrhythmias, leading to sudden cardiac death.
Question 3: Tolerance to opioids develops MOST rapidly with which effect?
- Analgesia and euphoria (Correct answer)
- Constipation
- Pupillary constriction (miosis)
- Cough suppression
Correct answer: Analgesia and euphoria
Tolerance develops rapidly to opioid analgesia and euphoria, while constipation and miosis show minimal tolerance—explaining why long-term users remain constipated.
Question 4: Which statement BEST describes the pharmacokinetic difference between crack cocaine and powder cocaine?
- Crack cocaine is absorbed more slowly via nasal mucosa
- Crack cocaine is smoked, reaching the brain faster and producing a more intense but shorter high (Correct answer)
- Powder cocaine produces stronger effects because it is injected more often
- Both forms have identical onset and duration regardless of route
Correct answer: Crack cocaine is smoked, reaching the brain faster and producing a more intense but shorter high
Smoking crack cocaine delivers the drug to the brain in seconds via pulmonary absorption, creating a rapid, intense rush that dissipates quickly, reinforcing compulsive redosing.
Question 5: A client prescribed buprenorphine reports precipitated withdrawal after their first dose. This MOST likely occurred because:
- Buprenorphine has a very long half-life that overwhelmed their system
- The client used a long-acting opioid and was not sufficiently withdrawn before induction (Correct answer)
- Naloxone in the formulation was absorbed sublingually
- They were opioid-naïve and had no tolerance
Correct answer: The client used a long-acting opioid and was not sufficiently withdrawn before induction
Buprenorphine's high receptor affinity displaces full opioid agonists that still occupy receptors; if induction begins too early, this displacement precipitates acute withdrawal.
Question 6: Gamma-hydroxybutyrate (GHB) is endogenously produced in the brain and acts primarily on:
- Dopamine D1 receptors
- GABA-B receptors and GHB-specific receptors (Correct answer)
- Nicotinic acetylcholine receptors
- Kappa-opioid receptors
Correct answer: GABA-B receptors and GHB-specific receptors
GHB acts on GABA-B receptors and specific GHB receptors, producing CNS depression; its narrow therapeutic window makes overdose particularly dangerous.
Question 7: The concept of 'reverse tolerance' or sensitization is MOST associated with which substance and effect?
- Alcohol and liver toxicity
- Cocaine and psychosis/seizure susceptibility with repeated use (Correct answer)
- Heroin and respiratory depression
- Cannabis and anxiety reduction
Correct answer: Cocaine and psychosis/seizure susceptibility with repeated use
With repeated cocaine use, sensitization (reverse tolerance) can develop for psychotic symptoms and seizures, meaning smaller doses can trigger these effects over time.
MAC Pharmacology of Substances 4
MDMA (ecstasy) primarily exerts its psychoactive effects by causing massive release and reuptake inhibition of: