LCAS Pharmacology of Addictive Substances

Question 1

Which neurotransmitter is most centrally involved in the mesolimbic reward pathway associated with substance use disorders?

Accepted Answer

Dopamine

Answer

Serotonin

Answer

GABA

Answer

Norepinephrine

Question 2

Which of the following correctly describes the primary mechanism of action of opioids in the central nervous system?

Accepted Answer

They bind to mu, kappa, and delta opioid receptors

Answer

They block dopamine reuptake in the nucleus accumbens

Answer

They enhance GABA-A receptor chloride conductance

Answer

They antagonize NMDA glutamate receptors

Question 3

Alcohol produces CNS depression primarily by which pharmacological mechanism?

Accepted Answer

Enhancing GABA-A inhibitory activity and inhibiting NMDA glutamate receptors

Answer

Blocking dopamine D2 receptors

Answer

Stimulating serotonin 5-HT3 receptors exclusively

Answer

Blocking norepinephrine reuptake transporters

Question 4

In addiction pharmacology, 'tolerance' is best defined as:

Accepted Answer

The requirement for increasing doses to achieve the same effect previously produced by a lower dose

Answer

The ability to function normally despite intoxication

Answer

Physical symptoms that occur when drug use is discontinued

Answer

The psychological craving for a substance between uses

Question 5

Which opioid's long half-life (24–36 hours) produces withdrawal symptoms that are less intense but more prolonged compared to short-acting opioids?

Accepted Answer

Methadone

Answer

Heroin

Answer

Hydrocodone

Answer

Oxycodone

Question 6

The concurrent use of two or more psychoactive substances is clinically referred to as:

Accepted Answer

Polysubstance use

Answer

Cross-tolerance

Answer

Synergism

Answer

Potentiation

Question 7

Stimulants such as cocaine and amphetamines primarily produce euphoria by which mechanism?

Accepted Answer

Blocking the reuptake of dopamine, norepinephrine, and serotonin

Answer

Binding to opioid receptors in the limbic system

Answer

Enhancing GABA-A inhibitory postsynaptic potentials

Answer

Directly activating cannabinoid CB1 receptors