Mebendazole exerts its antiparasitic effects through the following mechanisms:

1. Microtubule Inhibition:
   • Binds to beta-tubulin in parasitic cells, inhibiting microtubule polymerization (Lippincott).
   • Disrupts glucose uptake and intracellular transport, leading to energy depletion and parasite death (Lange).
2. Selective Toxicity:
   • Higher affinity for parasite tubulin than human tubulin, minimizing host toxicity (BNF).

Mebendazole is indicated for:

1. Intestinal Helminth Infections:
   • Pinworms (Enterobius vermicularis): Single-dose treatment.
   • Roundworms (Ascaris lumbricoides), Hookworms (Ancylostoma duodenale, Necator americanus), and Whipworms (Trichuris trichiura): 3-day course (BNF).
2. Off-Label Uses:
   • Hydatid disease (caused by Echinococcus granulosus) and capillariasis, though albendazole is often preferred (Lippincott).

Dosage varies by infection type and patient age. Always follow prescribing guidelines:

Adults and Children Over 2 Years:

• Pinworms: 100 mg single dose, repeated after 2 weeks if reinfection occurs.
• Roundworms, Hookworms, Whipworms: 100 mg twice daily for 3 days (BNF).

Administration Tips:

• Tablets may be chewed, swallowed whole, or crushed with food.
• Fatty meals enhance absorption (Lange).

Mebendazole is generally well-tolerated, but potential side effects include:

Common:

• Gastrointestinal: Abdominal pain, diarrhea, nausea.
• Dizziness or headache.

Rare but Serious:

• Hepatotoxicity: Elevated liver enzymes (Lippincott).
• Hematologic Effects: Neutropenia, agranulocytosis (BNF).
• Hypersensitivity Reactions: Rash, angioedema.

Before using mebendazole, consider:

• Pregnancy: Avoid in the first trimester; use only if benefits outweigh risks (BNF Category: C).
• Breastfeeding: Low systemic absorption minimizes risk; generally considered safe.
• Hepatic Impairment: Monitor for toxicity due to altered metabolism.
• Hygiene Measures: Wash bedding and clothing to prevent reinfection, especially in pinworm cases (Lange).

Mebendazole interacts with:

1. CYP450 Inhibitors (e.g., cimetidine):
   • Increase mebendazole levels, enhancing efficacy and toxicity risk (BNF).
2. CYP450 Inducers (e.g., carbamazepine, phenytoin):
   • Reduce mebendazole levels, decreasing effectiveness (Lippincott).
3. Metronidazole:
   • Avoid concurrent use due to rare reports of Stevens-Johnson syndrome (Lange).

Generic Names in Pharmacy

• Mebendazole (active ingredient)
• Common brand names: Vermox®, Ovex®, Emverm®