Which drug is commonly used to treat giardiasis?

Metronidazole is the commonly used drug for treating giardiasis, an intestinal infection caused by the Giardia lamblia protozoan. Metronidazole works by inhibiting nucleic acid synthesis, which ultimately leads to the death of the protozoa. It is effective in alleviating the symptoms of giardiasis and clearing the infection from the gastrointestinal tract.

This drug has demonstrated efficacy in clinical settings and is often considered a first-line treatment. While other medications like albendazole may have some use against certain parasitic infections, they are not the primary choice for giardiasis. Ivermectin primarily targets nematodes and some ectoparasites, not Giardia. Praziquantel is effective for treating infections caused by schistosomes and other trematodes, but it does not work against giardiasis. Therefore, metronidazole stands out as the correct and most appropriate treatment option for giardiasis.