PSI Pharmacology & Therapeutics 2

Question 1

Which drug class is used as first-line for acute migraine attacks?

Accepted Answer

Triptans (5-HT1B/1D agonists)

Answer

Triptans (e.g., sumatriptan) selectively activate 5-HT1B/1D receptors causing cerebral vasoconstriction and inhibiting neuropeptide release, aborting migraine attacks.

Question 2

Which antibacterial mechanism does penicillin use?

Accepted Answer

Inhibition of bacterial cell wall synthesis

Answer

Penicillin irreversibly binds penicillin-binding proteins (PBPs), inhibiting cross-linking of peptidoglycan in the bacterial cell wall, leading to osmotic lysis of the bacterium.

Question 3

Selective serotonin reuptake inhibitors (SSRIs) treat depression by:

Accepted Answer

Blocking the serotonin transporter (SERT)

Answer

SSRIs block SERT, preventing reuptake of serotonin from the synapse, thereby increasing synaptic serotonin concentration and enhancing serotonergic neurotransmission.

Question 4

Which diuretic is potassium-sparing and acts by blocking aldosterone receptors?

Accepted Answer

Spironolactone

Answer

Spironolactone competitively antagonises aldosterone receptors in the collecting duct, reducing sodium reabsorption and potassium excretion. It is used in heart failure and hyperaldosteronism.

Question 5

Atorvastatin lowers LDL cholesterol primarily by:

Accepted Answer

Inhibiting HMG-CoA reductase in the liver

Answer

Statins inhibit HMG-CoA reductase, the rate-limiting enzyme in hepatic cholesterol synthesis. This upregulates LDL receptors, increasing LDL clearance from blood.

PSI Pharmacy Practice Test

PSI Pharmacy Practice Test

PSI Pharmacology & Therapeutics 2