CADC Alcohol and Drug Counselor Pharmacology of Psychoactive Substances 4 — Questions and Answers
Question 1: Which statement best describes the concept of physical dependence?
- A compulsive psychological need to use a substance despite consequences
- An adaptive physiological state where abstinence causes withdrawal symptoms (Correct answer)
- The inability to experience pleasure without using a substance
- A genetic predisposition to developing a substance use disorder
Correct answer: An adaptive physiological state where abstinence causes withdrawal symptoms
Physical dependence is an adaptive physiological state characterized by tolerance and withdrawal symptoms upon abrupt cessation of the substance.
Question 2: Cannabis produces its psychoactive effects primarily through:
- Activation of dopamine D2 receptors in the prefrontal cortex
- Binding to endocannabinoid CB1 receptors in the brain (Correct answer)
- Blockade of NMDA receptors in the limbic system
- Stimulation of serotonin 5-HT2A receptors in the cortex
Correct answer: Binding to endocannabinoid CB1 receptors in the brain
THC mimics endogenous cannabinoids by binding to CB1 receptors, which are found throughout the brain and mediate its psychoactive effects.
Question 3: A counselor is working with a client experiencing opioid overdose. Which medication should be administered immediately?
- Naltrexone
- Buprenorphine
- Naloxone (Narcan) (Correct answer)
- Methadone
Correct answer: Naloxone (Narcan)
Naloxone is a fast-acting opioid antagonist that rapidly reverses opioid overdose by displacing opioids from receptors.
Question 4: Cocaine's primary mechanism of action involves:
- Stimulating opioid receptors in the ventral tegmental area
- Blocking the reuptake of dopamine, serotonin, and norepinephrine at synapses (Correct answer)
- Directly releasing large amounts of dopamine from storage vesicles
- Inhibiting monoamine oxidase (MAO) enzyme activity
Correct answer: Blocking the reuptake of dopamine, serotonin, and norepinephrine at synapses
Cocaine blocks monoamine reuptake transporters (DAT, SERT, NET), causing accumulation of dopamine, serotonin, and norepinephrine in the synapse.
Question 5: Which factor most significantly influences a drug's ability to cross the blood-brain barrier?
- The drug's molecular weight and lipid solubility (Correct answer)
- The drug's color and physical state (solid vs. liquid)
- The presence of food in the stomach during ingestion
- The user's age and gender
Correct answer: The drug's molecular weight and lipid solubility
Lipid-soluble, small-molecular-weight drugs most readily cross the blood-brain barrier through passive diffusion.
Question 6: Methadone is effective for opioid use disorder maintenance treatment because it:
- Produces a rapid and intense high that satisfies cravings quickly
- Has a long half-life and produces stable blood levels that reduce cravings and withdrawal (Correct answer)
- Permanently desensitizes opioid receptors after 30 days of use
- Blocks all opioid receptors, making it impossible to experience any opioid effects
Correct answer: Has a long half-life and produces stable blood levels that reduce cravings and withdrawal
Methadone's long half-life (24-36 hours) allows once-daily dosing, stabilizes opioid receptor activity, and eliminates withdrawal and craving cycles.
Question 7: The term 'synergistic effect' in pharmacology refers to when two drugs:
- Compete for the same receptor site and cancel each other out
- Produce a combined effect greater than the sum of their individual effects (Correct answer)
- Metabolize each other, reducing their individual half-lives
- Produce identical effects through completely different mechanisms
Correct answer: Produce a combined effect greater than the sum of their individual effects
Synergism occurs when the combined effect of two drugs exceeds the additive sum of each drug's individual effect, which increases both therapeutic and dangerous potential.
CADC Alcohol and Drug Counselor Pharmacology of Psychoactive Substances 4
Which statement best describes the concept of physical dependence?