Which drug is commonly used to treat Strongyloides stercoralis infection?

• A. Albendazole
• B. Metronidazole
• C. Ivermectin
• D. Praziquantel

Answer: (C)

Ivermectin is used because it has reliable activity against Strongyloides stercoralis, including the adult worms and the larval stages that sustain autoinfection. It works by binding to glutamate-gated chloride channels in the parasite’s nerve and muscle cells, causing paralysis and death, which translates into high cure rates with generally well-tolerated therapy. For uncomplicated strongyloidiasis, the standard approach is an oral dose of 200 micrograms per kilogram, often given as a single dose and repeated after 1–2 weeks if needed. In severe or disseminated infection, therapy is extended and may be given daily until improvement and stool or larval clearance are achieved. Other drugs, like albendazole, can be used in some settings but are less consistently effective as monotherapy for Strongyloides; metronidazole and praziquantel target other organisms and are not appropriate for treating this infection.