Which antifungal drug is used to treat systemic fungal infections and can cause nephrotoxicity?

Choice A reason: Itraconazole is a systemic antifungal used for infections like histoplasmosis. It inhibits ergosterol synthesis but is not typically used topically for athlete’s foot due to its oral or intravenous administration. Its systemic use carries risks like hepatotoxicity, making it unsuitable for localized dermatophyte infections.

Choice B reason: Ketoconazole is available as a topical cream but is less commonly used for athlete’s foot compared to terbinafine. It inhibits fungal ergosterol synthesis and is effective for cutaneous infections, but its topical use is more associated with seborrheic dermatitis or candidiasis, not primarily tinea pedis.

Choice C reason: Terbinafine is a topical antifungal commonly used for athlete’s foot (tinea pedis). It inhibits squalene epoxidase, disrupting fungal cell membrane synthesis, leading to fungal death. Its topical application effectively treats dermatophyte infections like Trichophyton, making it a first-line choice for localized fungal infections.

Choice D reason: Amphotericin B is a systemic antifungal used for severe fungal infections. It binds to ergosterol, causing fungal cell lysis, but is not used topically for athlete’s foot due to its toxicity and intravenous administration. It is reserved for life-threatening systemic infections, not cutaneous conditions.

Choice A reason: Reducing raw vegetables and fruit is not necessary with simvastatin. Dietary vitamin K may affect warfarin, but statins are unaffected by fruits or vegetables, except grapefruit, which inhibits CYP3A4, increasing simvastatin levels. A balanced diet supports cardiovascular health, making this instruction incorrect.

Choice B reason: Drug interactions are not rare with simvastatin, a statin metabolized by CYP3A4. Inhibitors like grapefruit juice or antifungals increase simvastatin levels, risking toxicity, while inducers reduce efficacy. Patients must be educated about potential interactions, making this statement incorrect and misleading for safe statin use.

Choice C reason: Reporting muscle pain immediately is critical with simvastatin, as it may indicate myopathy or rare rhabdomyolysis. Statins disrupt muscle cell membranes, causing pain or weakness. Early reporting allows monitoring of creatine kinase levels and prevents progression to severe muscle damage, ensuring patient safety.

Choice D reason: Reporting bleeding or yellow skin (jaundice) is essential, as simvastatin can cause hepatotoxicity, elevating liver enzymes, or rare bleeding due to drug interactions. Jaundice indicates liver dysfunction, and bleeding may result from interactions with anticoagulants, necessitating prompt reporting to adjust therapy or monitor liver function.

Choice E reason: Limiting fluid intake is not required with simvastatin. Fluid overload is unrelated to statins, which affect cholesterol synthesis, not fluid balance. Adequate hydration supports general health, and no evidence suggests fluid restriction is necessary, making this instruction irrelevant and potentially harmful.