mebendazole /məben″dəzōl/ , an anthelmintic. ▪ INDICATIONS: It is prescribed in the treatment of pinworm, whipworm, roundworm, and hookworm infestations. ▪ CONTRAINDICATIONS: Pregnancy or known hypersensitivity to this drug prohibits its use. ▪ ADVERSE EFFECTS: Among the most serious adverse effects are abdominal pain and diarrhea.