CADC Alcohol and Drug Counselor Pharmacology of Psychoactive Substances 2 — Questions and Answers
Question 1: Which neurotransmitter system is primarily responsible for the reinforcing effects of opioids?
- Dopaminergic system in the mesolimbic pathway (Correct answer)
- Serotonergic system in the raphe nuclei
- GABAergic system in the cerebellum
- Cholinergic system in the basal ganglia
Correct answer: Dopaminergic system in the mesolimbic pathway
Opioids activate the mesolimbic dopamine pathway by disinhibiting dopamine neurons, producing reinforcing effects.
Question 2: Naltrexone is used in alcohol use disorder treatment primarily because it:
- Causes an aversive reaction when alcohol is consumed
- Blocks opioid receptors and reduces alcohol's rewarding effects (Correct answer)
- Increases GABA activity to reduce cravings
- Prevents alcohol from being metabolized in the liver
Correct answer: Blocks opioid receptors and reduces alcohol's rewarding effects
Naltrexone blocks mu-opioid receptors, reducing the euphoric and rewarding effects of alcohol consumption.
Question 3: Which of the following best describes the mechanism of action of benzodiazepines?
- They block dopamine reuptake transporters
- They potentiate GABA-A receptor activity, increasing chloride ion influx (Correct answer)
- They inhibit serotonin reuptake in the synapse
- They stimulate NMDA glutamate receptors
Correct answer: They potentiate GABA-A receptor activity, increasing chloride ion influx
Benzodiazepines bind to GABA-A receptors and enhance the effect of GABA, increasing chloride conductance and producing CNS depression.
Question 4: A client reports using methamphetamine and describes feeling extremely energetic and confident with a decreased need for sleep. These effects are primarily due to:
- Activation of opioid mu receptors
- Massive release and reuptake blockade of catecholamines (Correct answer)
- Enhancement of GABA inhibitory signaling
- Blockade of serotonin receptors in the cortex
Correct answer: Massive release and reuptake blockade of catecholamines
Methamphetamine causes massive release of dopamine, norepinephrine, and serotonin while also blocking their reuptake transporters.
Question 5: The half-life of a drug refers to:
- The time it takes for half the dose to be absorbed into the bloodstream
- The time required for the plasma concentration to decrease by 50% (Correct answer)
- The duration of the drug's peak therapeutic effect
- Half the total duration of the drug's psychoactive effect
Correct answer: The time required for the plasma concentration to decrease by 50%
Half-life is the time required for the concentration of a drug in the blood plasma to be reduced by half.
Question 6: Which of the following withdrawal syndromes is considered potentially life-threatening without medical intervention?
- Opioid withdrawal
- Cannabis withdrawal
- Cocaine withdrawal
- Alcohol withdrawal (Correct answer)
Correct answer: Alcohol withdrawal
Alcohol withdrawal can cause seizures, delirium tremens, and death, making it one of the few withdrawal syndromes that can be lethal.
Question 7: Disulfiram (Antabuse) produces its aversive effect by:
- Blocking alcohol from crossing the blood-brain barrier
- Inhibiting aldehyde dehydrogenase, causing acetaldehyde accumulation (Correct answer)
- Activating opioid receptors to create dysphoria
- Stimulating the vomiting center in the brainstem directly
Correct answer: Inhibiting aldehyde dehydrogenase, causing acetaldehyde accumulation
Disulfiram inhibits aldehyde dehydrogenase, causing toxic acetaldehyde to accumulate when alcohol is consumed, producing nausea and flushing.
CADC Alcohol and Drug Counselor Pharmacology of Psychoactive Substances 2
Which neurotransmitter system is primarily responsible for the reinforcing effects of opioids?