Mebendazole: what it treats, how to use it, and what to watch for

Mebendazole is a common anti-worm medicine used to treat intestinal parasites like pinworms, roundworms, whipworms and some hookworms. It works by stopping the parasite’s ability to use glucose, which weakens and kills the worm. Most people tolerate it well because little of the drug is absorbed into the bloodstream, but you still need to use it correctly and follow safety rules.

Quick dosing guide

Common dosing depends on the infection. For pinworms (enterobiasis) the typical dose is 100 mg as a single chewable tablet, repeated once after 2 weeks to catch reinfection from eggs. For roundworm, whipworm or hookworm, a common regimen is 100 mg twice daily for three days. Always follow the instructions from your doctor or the product label — some infections need different lengths of treatment.

Children: chewable 100 mg tablets are often used in kids, but age and weight limits vary by product and country. Don’t give mebendazole to an infant or pregnant person without a doctor’s ok. If in doubt, check with a pediatrician or pharmacist.

Side effects, warnings and interactions

Most side effects are mild: stomach pain, diarrhea, or nausea. Rare but serious issues include liver problems or low blood counts; tell your doctor if you have ongoing abdominal pain, yellowing skin, dark urine, unexplained bruising, or fever. Avoid mebendazole in early pregnancy — it’s generally not recommended during the first trimester. If you’re breastfeeding or have severe liver disease, get medical advice first.

Drug interactions are limited because systemic absorption is low, but always tell your clinician about other medicines you take. If your infection is severe or symptoms persist after treatment, your doctor may repeat testing or choose an alternative like albendazole or pyrantel pamoate.

Practical tips: wash hands often, trim nails, change and wash bedding and towels, and treat close contacts at the same time to reduce reinfection. For pinworms, vacuuming and daily morning showers for kids help remove eggs.

Buying mebendazole online: what to check

Mebendazole often requires a prescription. If you buy online, use a licensed pharmacy that asks for a prescription and has clear contact details, privacy policy and secure checkout (HTTPS). Avoid sites offering unusually low prices without prescription or pushing large quantities. Read real reviews and check pharmacy credentials in your country. If an online service includes a quick “no-visit” prescription, be cautious — legitimate services usually offer a proper consultation with a prescriber.

If you see ongoing symptoms such as blood in stool, weight loss, significant abdominal pain, or fever, see your doctor rather than self-treating. Proper diagnosis and follow-up keep treatment safe and effective.