mebendazol

Mebendazole is a broad-spectrum anthelmintic in the benzimidazole class, used to treat common intestinal worm infections caused by nematodes. It is commonly prescribed for ascariasis (roundworm), enterobiasis (pinworm), trichuriasis (whipworm), and hookworm infections. Its usefulness is largely limited to nematodes; it has little to no activity against cestodes (tapeworms) or trematodes (flukes).

The drug works by binding to parasite beta-tubulin and inhibiting microtubule formation. This disrupts the parasite’s ability to take up glucose and maintain energy stores, leading to energy depletion and death of the worms. Mebendazole is generally more effective against adult worms in the gut than against tissue stages, and its systemic absorption is low, which contributes to a favorable safety profile for many infections.

Mebendazole is taken orally and has very limited oral bioavailability; absorption increases when taken with fatty meals. After absorption, it is metabolized in the liver and excreted mainly in feces as metabolites, with only small amounts eliminated in urine. Dosing regimens vary by infection and by patient age; single-dose regimens are common for pinworm infections, while longer courses may be used for other nematodes. Local guidelines should be followed for specific indications and dosing.

Safety and cautions: Mebendazole is generally well tolerated. Common side effects include abdominal pain, nausea, and diarrhea; rare cases of liver injury or hypersensitivity have been reported. It should be avoided in pregnancy, especially in the first trimester, and used with caution during lactation. Availability varies by country and regulatory status, with some regions requiring prescription.