Mebendazole; Uses, Dosage, Side Effects, Interactions, Pregnancy

Last updated: February 7, 2026Reviewed date: February 7, 2026Reading time: 10 min read
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Mebendazole is a synthetic benzimidazole derivate an anthelmintic agent. Mebendazole interferes with the reproduction and survival of helminths by inhibiting the formation of their cytoplasmic microtubules, thereby selectively and irreversibly blocking glucose uptake. This results in a depletion of glycogen stores and leads to reduced formation of ATP required for survival and reproduction of the...

For severe symptoms, danger signs, pregnancy, child illness, or sudden worsening, seek urgent medical care.

বাংলা রোগী নোট এখনো যোগ করা হয়নি। পোস্ট এডিটরে “RX Bangla Patient Mode” বক্স থেকে সহজ বাংলা সারাংশ যোগ করুন।

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Article Summary

Mebendazole is a synthetic benzimidazole derivate an anthelmintic agent. Mebendazole interferes with the reproduction and survival of helminths by inhibiting the formation of their cytoplasmic microtubules, thereby selectively and irreversibly blocking glucose uptake. This results in a depletion of glycogen stores and leads to reduced formation of ATP required for survival and reproduction of the helminth. This eventually causes the helminths death.   Mebendazole is a (synthetic) broad-spectrum anthelmintic, member of the benzimidazole class of antiparasitic...

Key Takeaways

  • This article explains Mechanism of Action of Mebendazole in simple medical language.
  • This article explains Indications of Mebendazole in simple medical language.
  • This article explains Contra-Indications of Mebendazole in simple medical language.
  • This article explains Dosage of Mebendazole in simple medical language.
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Definition

Mebendazole is a synthetic benzimidazole derivate an anthelmintic agent. Mebendazole interferes with the reproduction and survival of helminths by inhibiting the formation of their cytoplasmic microtubules, thereby selectively and irreversibly blocking glucose uptake. This results in a depletion of glycogen stores and leads to reduced formation of ATP required for survival and reproduction of the helminth. This eventually causes the helminths death.

 

Mebendazole is a (synthetic) broad-spectrum anthelmintic, member of the benzimidazole class of antiparasitic agents, which also includes thiabendazole, albendazole, and triclabendazole & used to treat infections caused by worms such as whipworm, pinworm, roundworm, and hookworm. Mebendazole, like other benzimidazoles, causes the death of parasites by interfering with the function of tubulin, an important protein in parasites, and preventing glucose uptake.

Mechanism of Action of Mebendazole

Mebendazole causes degenerative alterations in the tegument and intestinal cells of the worm by binding to the colchicine-sensitive site of tubulin, thus inhibiting its polymerization or assembly into microtubules. The loss of the cytoplasmic microtubules leads to impaired uptake of glucose by the larval and adult stages of the susceptible parasites and depletes their glycogen stores. Degenerative changes in the endoplasmic reticulum, the mitochondria of the germinal layer, and the subsequent release of lysosomes result in decreased production of adenosine triphosphate (ATP), which is the energy required for the survival of the helminth. Due to diminished energy production, the parasite is immobilized and eventually dies.

Indications of Mebendazole

  • Pinworm Infection (Enterobius vermicularis)
  • Whipworm Infection
  • Ascariasis
  • Angiostrongylosis
  • Capillariasis
  • Dracunculiasis
  • Echinococcus
  • Filariasis, Elephantiasis
  • Hookworm Infection (Necator or Ancylostoma)
  • Hydatid Disease
  • Trichinosis
  • Trichostrongylosis
  • Visceral Larva Migrans, Toxocariasis
  • Ancylostoma caninum infection
  • Ancylostoma duodenale infection
  • Ascaris lumbricoides infection
  • Capillariasis
  • Enterobius vermicularis infection
  • Giardiasis
  • Necatoriasis due to necator americanus
  • Strongyloides Stercoralis Infection
  • Taenia solium infection
  • Toxocariasis
  • Whipworm infection
  • For the treatment of Enterobius vermicularis (pinworm), Trichuris trichiura (whipworm), Ascaris lumbricoides (common roundworm), Ancylostoma duodenale (common hookworm), Necator americanus (American hookworm) in single or mixed infections.

Therapeutic Indications of Mebendazole

  • Mebendazole is indicated as a primary agent for tichuriasis caused by Trichuris trichiura (whipworm).
  • Mebendazole is indicated in the treatment of multiple intestinal roundworm infections.
  • Mebendazole is indicated a primary agent for enterobiasis caused by Enterobius vermicularis (pinworm).
  • Mebendazole is used as a secondary agent in the treatment of trichinosis (trichinellosis) caused by Trichinella spiralis (pork worm). Systemic corticosteroids are used concurrently, especially in patients with severe symptoms, to minimize inflammatory reactions to Trichinella larvae. Echinococcus multilocularis (E. alveolaris).
  • Mebendazole is used in the treatment of gnathostomiasis caused by Gnathostoma spinigerum.
  • Mebendazole is used in the treatment of unilocular hydatid disease caused by E. granulosus. Mebendazole is used as a secondary agent in patients in whom surgery is contraindicated or has failed, in after-spill during surgery, or in recurrences. Very high doses may be effective.
  • Mebendazole is used in the treatment of capillariasis caused by Capillaria phillippinensis.
  • Mebendazole is indicated as a primary agent for hookworm disease caused by Ancylostoma duodenale (common hookworm; Old World hookworm) and Necator americanus (American hookworm; New World hookworm).
  • Mebendazole is indicated as a primary agent for ascariasis caused by Ascaris lumbricoides (common roundworm).

Contra-Indications of Mebendazole

  • Reduction in the body’s resistance to infection
  • The acquired decrease of all cells in the blood
  • Low Blood counts due to bone marrow failure
  • Decreased neutrophils a type of white blood Cell
  • Liver Problems
  • Abnormal Liver Function Tests

Dosage of Mebendazole

Strengths

Tablet, chewable : 100mg  ;500mg

Usual Adult Dose

Hookworm Infection (Necator or Ancylostoma)

  • 100 mg orally twice a day for 3 days.
Whipworm Infection (Trichuris trichiura)
  • 100 mg orally twice a day for 3 days.

Pinworm Infection (Enterobius vermicularis)

  • 100 mg orally one time. This dose should be repeated in 2 weeks. All family members and close contacts should also be examined.

Angiostrongylosis

  • 100 mg orally twice a day for 5 days.

Ascariasis

  • 100 mg orally twice a day for 3 days.
  • If the biliary obstruction is also present, piperazine citrate 150 mg/kg initially, followed by 65 mg/kg every 12 hours for 6 doses by nasogastric tube is also recommended.

Capillariasis

  • 200 mg orally twice a day for 20 days. Relapses may be treated with prolonged courses of therapy.

Trichostrongylosis

  • 100 mg orally twice a day for 3 days.

Filariasis

  • 100 mg orally one time. This dose should be repeated in 2 weeks. All family members and close contacts should also be examined.
  • Mansonella perstans infection – 100 mg twice daily for 30 days.

Trichinosis

  • 200 to 400 mg orally three times a day for 3 days, then 400 to 500 mg three times a day for 10 days. Concomitant steroid therapy may be administered if the patient is symptomatic.

Visceral Larva Migrans (Toxicariasis)

  • 100 to 200 mg orally twice daily for 5 days. Coadministration of infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।" data-rx-term="inflammation" data-rx-definition="Inflammation is the body’s response to injury, infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।">inflammation, pain, or swelling. সহজ বাংলা: প্রদাহ/ফোলা/ব্যথা কমায়।" data-rx-term="anti-inflammatory" data-rx-definition="Anti-inflammatory means reducing inflammation, pain, or swelling. সহজ বাংলা: প্রদাহ/ফোলা/ব্যথা কমায়।">anti-inflammatory agents might be considered.

Echinococcus Infection

  • Hepatic Cystic infection -: 40 to 50 mg/kg per day, administered in three divided doses,

Hydatid Disease

  • Hepatic Cystic infection: 40 to 50 mg/kg per day, administered in three divided doses, Usual Adult Dose for Dracunculiasis
  • 400 to 800 mg per day for 6 days.

Pediatric Dose

Hookworm Infection (Necator or Ancylostoma)

  • Nausea
  • Greater than or equal to 2 years: 100 mg orally twice a day for 3 days.
Whipworm Infection (Trichuris trichiura)
  • Greater than or equal to 2 years: 100 mg orally twice a day for 3 days.
Pinworm Infection (Enterobius vermicularis)
  • Greater than or equal to 2 years: 100 mg orally one time. This dose should be repeated in 2 weeks. All family members and close contacts should also be examined.

Angiostrongylosis

  • Greater than or equal to 2 years: 100 mg orally twice a day for 5 days.

Ascariasis

  • Greater than or equal to 2 years: 100 mg orally twice a day for 3 days. If the biliary obstruction is also present, piperazine citrate 150 mg/kg initially, followed by 65 mg/kg every 12 hours for 6 doses by nasogastric tube is also recommended.

Capillariasis

  • Greater than or equal to 2 years: 200 mg orally twice a day for 20 days. Relapses may be treated with prolonged courses of therapy.

Filariasis

  • Greater than or equal to 2 years: 100 mg orally one time. This dose should be repeated in 2 weeks. All family members and close contacts should also be examined.
  • Mansonella perstans infection – 100 mg twice daily for 30 days.

Trichinosis

  • Greater than or equal to 2 years: 200 to 400 mg orally three times daily for 3 days, then 400 to 500 mg three times daily for 10 days. Steroids may be administered if the patient is symptomatic.

Visceral Larva Migrans (Toxicariasis)

  • Greater than or equal to 2 years: 100 to 200 mg orally twice daily for 5 days. Coadministration of infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।" data-rx-term="inflammation" data-rx-definition="Inflammation is the body’s response to injury, infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।">inflammation, pain, or swelling. সহজ বাংলা: প্রদাহ/ফোলা/ব্যথা কমায়।" data-rx-term="anti-inflammatory" data-rx-definition="Anti-inflammatory means reducing inflammation, pain, or swelling. সহজ বাংলা: প্রদাহ/ফোলা/ব্যথা কমায়।">anti-inflammatory agents might be considered.

Side Effects of Mebendazole

The most common

Common

Serious

Drug Interactions of Mebendazole

Barbiturates: (Moderate) Barbiturates induce hepatic microsomal enzymes and may increase the metabolism of mebendazole if given concomitantly. This effect can cause decreased levels of plasma mebendazole but is probably important only in the treatment of extraintestinal infections, such as hydatid cyst disease, and not in the treatment of intestinal helminths.
Bismuth Subcitrate Potassium; Metronidazole; Tetracycline: (Major) Avoid the concomitant use of mebendazole and metronidazole. Serious skin reactions, such as Stevens-Johnson syndrome and toxic epidermal necrolysis, have been reported with coadministration.
Bismuth Subsalicylate; Metronidazole; Tetracycline: (Major) Avoid the concomitant use of mebendazole and metronidazole. Serious skin reactions, such as Stevens-Johnson syndrome and toxic epidermal necrolysis, have been reported with coadministration.
Carbamazepine: (Moderate) Carbamazepine may potentially accelerate the hepatic metabolism of mebendazole. Dosage adjustments may be necessary, and closer monitoring of clinical and/or adverse effects is warranted when carbamazepine is used with mebendazole.
Cimetidine: (Minor) Cimetidine may reduce the metabolism of mebendazole and increase mebendazole serum concentrations. Adverse hematological effects have been observed during concurrent use of cimetidine with high doses or prolonged mebendazole therapy. In a study of 7 patients, cimetidine significantly increased mebendazole concentrations; however, it was not considered to be of therapeutic relevance. In another study of 8 patients, concomitant use of cimetidine and a 30-day mebendazole treatment regimen resulted in a significant increase in mebendazole serum concentrations.
Fosphenytoin: (Moderate) Mebendazole is metabolized by hepatic cytochrome P450 enzymes and other enzymes. Fosphenytoin induces hepatic microsomal enzymes and may increase the metabolism of mebendazole if given concomitantly.
Metronidazole: (Major) Avoid the concomitant use of mebendazole and metronidazole. Serious skin reactions, such as Stevens-Johnson syndrome and toxic epidermal necrolysis, have been reported with coadministration.
Phenytoin: (Moderate) Hydantoin anticonvulsants induce hepatic microsomal enzymes and may increase the metabolism of other drugs, including mebendazole, leading to reduced efficacy of the concomitant medication.
Rifamycins: (Moderate) Mebendazole is metabolized by hepatic cytochrome P450 enzymes and other enzymes. Rifamycins induce hepatic microsomal enzymes and may increase the metabolism of mebendazole if given concomitantly.

Pregnancy and Lactation of Mebendazole

FDA Pregnancy Category C

Pregnancy

Since Vermox is contra-indicated in pregnancy, patients who think they are, or may be, pregnant should not take this preparation.

Lactation

As it is not known whether mebendazole is excreted in human milk, it is not advisable to breastfeed following administration of Vermox.

References

 

Mebendazole; Uses, Dosage, Side Effects, Interactions, Pregnancy

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Questions to ask
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Care roadmap for: Mebendazole; Uses, Dosage, Side Effects, Interactions, Pregnancy

Use this simple roadmap to understand the next safe steps. It is educational and does not replace examination by a doctor.

Go to emergency care if you notice:
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  • Breathing difficulty, chest pain, fainting, confusion, severe weakness, major injury, or severe dehydration
Doctor / service to discuss: Qualified healthcare provider; specialist depends on symptoms and examination.
  1. Step 1

    Check danger signs first

    If danger signs are present, seek emergency care and do not wait for online information.

  2. Step 2

    Record the symptom story

    Write when symptoms started, severity, medicines already taken, allergies, pregnancy status, and test results.

  3. Step 3

    Visit a qualified clinician

    A doctor, nurse, or qualified healthcare provider can examine you and decide which tests or treatment are needed.

  4. Step 4

    Do only useful tests

    Do tests after clinical assessment. Avoid unnecessary tests, random antibiotics, or repeated medicines without diagnosis.

  5. Step 5

    Follow up and return early if worse

    If symptoms worsen, new warning signs appear, or treatment is not helping, return for review quickly.

Rural patient practical tips
  • Take a written symptom diary and all previous prescriptions/test reports.
  • Do not hide medicines already taken, even herbal or over-the-counter medicines.
  • Ask which warning signs mean urgent referral to hospital.

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