Mebendazole
Class
Indications
Nematode infections
Administration/Absorption
Oral
Poorly absorbed (approximately 5 to 10%) from gastrointestinal tract
Fatty food increases absorption
Dosage
Pinworms: 100 mg once
Whipworm, common roundworm and hookworm: 100 mg BD for 3 days
Distribution
90-95% protein bound
Mechanism
Selectively inhibits the synthesis of microtubules in parasitic worms
=> destroys extant cytoplasmic microtubes in their intestinal cells
Thereby blocks the uptake of glucose and other nutrients
Results in the gradual immobilization and eventual death of the helminths
Excretion
Primarily hepatic metabolism
Half life 2.5 to 5.5 hours
Side effects
Transient abdominal pain, diarrhea, slight headache, fever, dizziness, exanthema, urticaria and angioedema
Interactions
Carbamazepine and phenytoin lower serum levels of mebendazole
Stevens–Johnson syndrome can occur when mebendazole is combined with high doses of metronidazole
Contraindications
Pregnancy
Embryotoxic and teratogenic in experimental animals