MAC Pharmacology of Substances 5

Question 1

When comparing methadone and buprenorphine for opioid use disorder treatment, which statement about overdose risk is MOST accurate?

Accepted Answer

Methadone carries higher overdose risk due to its full agonist activity, long half-life, and QTc prolongation

Answer

Methadone's full agonist activity combined with its variable and long half-life (24–60 hours) and QTc-prolonging effects make it more dangerous in overdose than buprenorphine, which has a ceiling effect on respiratory depression.

Question 2

A client describes using LSD and experiencing 'flashbacks' weeks later without taking the drug again. This phenomenon is clinically known as:

Accepted Answer

Hallucinogen Persisting Perception Disorder (HPPD)

Answer

HPPD involves spontaneous re-experiencing of perceptual disturbances (visual distortions, geometric hallucinations) weeks to years after hallucinogen use, without taking the substance again.

Question 3

Nicotine's primary mechanism of physical dependence involves:

Accepted Answer

Upregulation of nicotinic acetylcholine receptors (nAChRs) in the brain due to chronic stimulation

Answer

Chronic nicotine exposure causes upregulation (increased density) of nAChRs; when nicotine is absent, these receptors are understimulated, producing withdrawal symptoms.

Question 4

Varenicline (Chantix) reduces nicotine cravings and withdrawal by acting as a:

Accepted Answer

Partial agonist at alpha-4 beta-2 nicotinic acetylcholine receptors

Answer

Varenicline is a partial agonist at alpha-4 beta-2 nAChRs, providing enough receptor stimulation to reduce cravings while blocking nicotine's ability to produce full reward if the client smokes.

Question 5

A client with opioid use disorder and chronic pain is being considered for buprenorphine. The counselor should understand that buprenorphine's analgesic effectiveness is BEST described as:

Accepted Answer

Effective for both OUD and pain, though pain dosing is typically more frequent (TID-QID)

Answer

Buprenorphine provides effective analgesia but its analgesic duration (6–8 hours) is shorter than its OUD dosing duration (24 hours), so pain management may require more frequent administration.

Master Addiction Counselor Exam Practice Test

Master Addiction Counselor Exam Practice Test

MAC Pharmacology of Substances 5