CARN Pharmacology of Addictive Substances 2

Question 1

Which receptor subtype is primarily responsible for the euphoric effects of opioids?

Accepted Answer

Mu (μ)

Answer

Kappa (κ)

Answer

Delta (δ)

Answer

Sigma (σ)

Question 2

A patient on buprenorphine/naloxone reports that injecting the medication produces little to no euphoria. Which pharmacological property of naloxone best explains this?

Accepted Answer

Naloxone blocks opioid receptors when administered parenterally

Answer

Naloxone has a longer half-life than buprenorphine

Answer

Naloxone induces CYP3A4 metabolism of buprenorphine

Answer

Naloxone causes histamine release that blunts reward

Question 3

Cocaine's primary mechanism of action involves blocking the reuptake of which neurotransmitter most responsible for its reinforcing effects?

Accepted Answer

Dopamine

Answer

Serotonin

Answer

GABA

Answer

Norepinephrine

Question 4

Which benzodiazepine property makes diazepam particularly prone to misuse compared to oxazepam?

Accepted Answer

Diazepam has a faster onset of action due to higher lipophilicity

Answer

Diazepam has active metabolites; oxazepam does not

Answer

Diazepam requires hepatic glucuronidation; oxazepam does not

Answer

Diazepam has higher protein binding than oxazepam

Question 5

Which mechanism explains why alcohol withdrawal can be life-threatening, unlike opioid withdrawal?

Accepted Answer

Alcohol causes upregulation of GABA-A receptors leading to CNS hyperexcitability upon cessation

Answer

Alcohol downregulates dopamine receptors causing severe dysphoria

Answer

Alcohol depletes glycogen stores leading to fatal hypoglycemia

Answer

Alcohol causes permanent destruction of serotonin neurons

Question 6

Naltrexone reduces alcohol cravings primarily by which pharmacological mechanism?

Accepted Answer

Blocking opioid receptors that mediate alcohol-induced dopamine release

Answer

Blocking NMDA glutamate receptors

Answer

Inhibiting aldehyde dehydrogenase to cause aversive reactions

Answer

Enhancing GABA-A receptor activity to reduce anxiety

Question 7

A patient who smokes methamphetamine develops severe hyperthermia and rhabdomyolysis. Which pharmacological mechanism most directly contributes to hyperthermia?

Accepted Answer

Massive norepinephrine release causing peripheral vasoconstriction and excess heat retention

Answer

Direct toxicity to the hypothalamic temperature set-point

Answer

Dopamine receptor overstimulation in the motor cortex

Answer

Inhibition of monoamine oxidase preventing heat dissipation