Classifications: antiinfective; anthelmintic
Prototype: Mebendazole
Pregnancy Category: C


250 mg capsules


Hydroquinone derivative prepared in the presence of Aspergillus sclerotium. Mechanism of action not fully explained, but it appears that drug-induced strong contractions and paralysis of worm musculature leads to immobilization of their suckers and dislodgment from their usual residence in mesenteric veins to the liver.

Therapeutic Effects

Dislodgment of schistosomes begins about 2 d after single oral dose; movement is not complete until 6 d after treatment with the drug. After treatment, surviving unpaired females return to mesenteric vessels; however, oviposition (egg laying) seems to stop in 24–48 h after drug treatment, reducing egg load and removing principal cause of pathology associated with schistosomal infection.


All stages of Schistosoma mansoni infection, including acute and chronic phases with hepatosplenic involvement.


Safe use during pregnancy (category C), lactation, or in children is not established.

Cautious Use

History of convulsant disorders.

Route & Dosage

Adult: PO 12–15 mg/kg as single dose
Child: PO <30 kg, 10 mg/kg times 2 doses at 2–8 h intervals



Adverse Effects (1%)

CNS: Transitory dizziness, drowsiness, headache; persistent fever (in patients being treated in Egypt); EEG abnormalities, convulsions (rare). GI: Anorexia, nausea, vomiting, abdominal pain, elevated liver enzyme concentrations. Hematologic: Increased erythrocyte sedimentation rate, reticulocyte count, and increased or decreased leukocyte count. Skin: Urticaria. Urogenital: Red-orange urine.


Food: Rate and extent of absorption are decreased by food.


Absorption: Readily absorbed from GI tract. Peak: 1–3 h. Metabolism: Extensively metabolized in GI mucosa. Elimination: Excreted in urine. Half-Life: 1–2.5 h.

Nursing Implications

Assessment & Drug Effects

Patient & Family Education

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug