NCCPA Pharmacology 2

Question 1

A patient on warfarin is started on fluconazole. What is the expected effect on INR?

Accepted Answer

INR increases due to CYP2C9 inhibition

Answer

Fluconazole inhibits CYP2C9, which metabolizes warfarin, leading to elevated warfarin levels and increased INR.

Question 2

Which beta-blocker is most cardioselective and preferred in a patient with reactive airway disease who requires beta-blockade?

Accepted Answer

Metoprolol succinate

Answer

Metoprolol succinate has the highest beta-1 selectivity among common beta-blockers, making it preferable in patients with reactive airway disease.

Question 3

A patient taking lithium develops polyuria and polydipsia. Which medication can reduce lithium-induced nephrogenic diabetes insipidus?

Accepted Answer

Amiloride

Answer

Amiloride blocks ENaC channels in collecting ducts, reducing lithium entry into renal tubular cells and alleviating nephrogenic DI.

Question 4

Which opioid analgesic is contraindicated in patients with renal failure due to accumulation of a toxic metabolite?

Accepted Answer

Meperidine

Answer

Meperidine's metabolite normeperidine accumulates in renal failure and can cause seizures and CNS excitation.

Question 5

A patient on isoniazid develops peripheral neuropathy. What is the recommended treatment?

Accepted Answer

Pyridoxine (vitamin B6) supplementation

Answer

Isoniazid causes pyridoxine deficiency by inhibiting its activation, and supplementation with vitamin B6 prevents and treats peripheral neuropathy.

(NCCPA) National Commission on Certification of Physician Assistants Practice Test