Vetdrugs 2.0Mebendazole is a benzimidazole anthelmintic used against susceptible gastrointestinal worms. Veterinary applications include selected intestinal nematodes in dogs and horses and some canine cestode infections. It is an older deworming agent whose practical spectrum depends on the parasite, developmental stage and treatment regimen. Much of its activity occurs within the gastrointestinal tract.
Group
Benzimidazole anthelmintic
Mechanism of Action
Mebendazole binds parasite beta-tubulin and inhibits microtubule assembly. Disruption of microtubule-dependent transport interferes with nutrient absorption and glucose utilization, progressively depleting energy stores and impairing parasite survival. These effects account for activity against susceptible intestinal worms. The relative affinity of benzimidazoles for parasite tubulin contributes to selective anthelmintic action.
Dose Rates
Dogs
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Intestinal worms | 22 mg/kg | PO | Every 24 h | Up to 3 days; Give with food; course may be repeated after 3 weeks. |
Horses
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Intestinal worms | 8.8 mg/kg | PO | Once |
Indications
- Treatment of susceptible canine roundworm, hookworm and whipworm infections, including Toxocara, Ancylostoma, Uncinaria and Trichuris species.
- Treatment of selected canine Taenia infections with a supported cestocidal regimen.
- Treatment of susceptible equine strongyles, ascarids and pinworms.
Contraindications
- Use cautiously if hepatic injury is suspected.
Interactions
- No specific veterinary interaction is established in the supplied material.
Adverse effects
- Occasional vomiting or diarrhoea
- Possible idiosyncratic hepatic injury in dogs
Toxicity
Assess gastrointestinal and hepatic signs after excess exposure.
Preparations
| Preparation | Form | Strength | Route |
|---|---|---|---|
| Mebendazole 100 mg tablet | Tablet | 100 mg / tablet | PO |
| Mebendazole 40 mg/g powder | Powder | 40 mg / g | PO |
| Mebendazole 166.7 mg/g powder | Powder | 166.7 mg / g | PO |
| Mebendazole 200 mg/g paste | Paste | 200 mg / g | PO |
| Mebendazole 33.3 mg/mL oral suspension | Oral Liquid | 33.3 mg / mL | PO |
Monitoring and Administration
Can be mixed with food. Equine powder may be given on grain or by a correctly prepared stomach-tube suspension.
Do not treat mebendazole-trichlorfon combinations as mebendazole-alone dosing.
Equine combination powders contain either mebendazole 83.3 mg/g plus trichlorfon 375 mg/g, or mebendazole 100 mg/g plus trichlorfon 454 mg/g. They require combination-specific assessment and must not be used as mebendazole-alone preparations.