Pharmacology & Therapeutics Flashcards

A DPM prescribes methotrexate for a patient with psoriatic arthritis affecting the feet. Which vitamin supplementation is routinely co-prescribed to reduce toxicity?

Answer: Folic acid

Folic acid supplementation reduces methotrexate-associated mucositis, cytopenias, and hepatotoxicity without significantly reducing its efficacy.

Efinaconazole (Jublia) is a topical azole approved for onychomycosis. How does it differ from older topical antifungals like ciclopirox?

Answer: It has superior nail plate penetration due to low affinity for keratin

Efinaconazole's low keratin binding affinity allows greater penetration through the nail plate to reach the nail bed where fungi reside.

A patient with type 2 diabetes and peripheral arterial disease is started on cilostazol for claudication. What is its mechanism of action?

Answer: Inhibits phosphodiesterase III, increasing cAMP in platelets and vascular smooth muscle

Cilostazol is a PDE III inhibitor that increases platelet and vascular smooth muscle cAMP, inhibiting platelet aggregation and causing vasodilation.

Which local anesthetic is an ESTER (not amide) type and is most likely to cause an allergic reaction due to its PABA metabolite?

Answer: Procaine

Procaine is an ester-type local anesthetic metabolized to PABA, which is a known allergen responsible for hypersensitivity reactions.

A podiatrist treating a patient with rheumatoid arthritis notices foot joint involvement. The patient is on a TNF-alpha inhibitor. Which infection risk must be screened before initiating this therapy?

Answer: Latent tuberculosis

TNF-alpha is critical for granuloma maintenance; its inhibition can reactivate latent TB, so tuberculin skin testing or IGRA is required before initiation.

Which systemic antifungal used for severe nail or skin fungal infections inhibits lanosterol 14-alpha-demethylase (CYP51) in fungi?

Answer: Itraconazole

Itraconazole and all azole antifungals inhibit fungal CYP51 (lanosterol 14-alpha-demethylase), blocking ergosterol synthesis and disrupting the fungal membrane.

A patient on long-term NSAIDs for foot arthritis develops a peptic ulcer. Which co-medication would BEST reduce this gastrointestinal risk if NSAID therapy must continue?

Answer: Proton pump inhibitor (e.g., omeprazole)

Proton pump inhibitors are the most effective agents for preventing NSAID-induced peptic ulcers and are recommended for high-risk patients requiring continuous NSAID use.