Antimicrobial and Chemotherapeutic Agents Flashcards
7 cards from real Pharmacology practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Antimicrobial and Chemotherapeutic Agents flashcards as text
A patient taking isoniazid (INH) for tuberculosis develops peripheral neuropathy. This adverse effect is best prevented by supplementing with:
Answer: Pyridoxine (Vitamin B6)
INH inhibits pyridoxal phosphate synthesis and competes with pyridoxine, causing peripheral neuropathy that is prevented by concurrent pyridoxine supplementation.
Which antibiotic class is contraindicated in children under 8 years of age due to risk of permanent tooth discoloration?
Answer: Tetracyclines
Tetracyclines bind to calcium in developing teeth and bones, causing permanent yellow-gray-brown discoloration and enamel hypoplasia in children under 8.
Trimethoprim-sulfamethoxazole (TMP-SMX) inhibits bacterial folate synthesis by blocking which two sequential steps?
Answer: Dihydropteroate synthase and dihydrofolate reductase
Sulfamethoxazole inhibits dihydropteroate synthase while trimethoprim inhibits dihydrofolate reductase; together they create sequential blockade of folate synthesis.
Which antiviral drug is used as prophylaxis and treatment for influenza A and B and works by inhibiting neuraminidase?
Answer: Oseltamivir
Oseltamivir (Tamiflu) inhibits viral neuraminidase, preventing release of new virions from infected cells and limiting spread of influenza A and B.
A patient develops gray baby syndrome after receiving which antibiotic?
Answer: Chloramphenicol
Chloramphenicol causes gray baby syndrome in neonates because their immature hepatic glucuronyl transferase cannot metabolize the drug, leading to toxic accumulation.
Which antiparasitic drug is first-line for treatment of malaria caused by chloroquine-resistant Plasmodium falciparum?
Answer: Artemether-lumefantrine
Artemisinin-based combination therapies (ACTs) such as artemether-lumefantrine are WHO first-line treatment for chloroquine-resistant P. falciparum malaria.
What is the primary mechanism by which bacteria develop resistance to aminoglycosides?
Answer: Production of modifying enzymes (acetyltransferases, phosphotransferases)
The most common mechanism of aminoglycoside resistance is production of plasmid-encoded enzymes that acetylate, phosphorylate, or adenylate the drug, preventing ribosomal binding.