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Terms Of Use


Brand Name(s) : Ovex, Pripsen, Vermox
Side Effects


Mebendazole should be used with caution in: women who are breastfeeding, or children under 2 years of age.

It should not be used in: pregnant women.

Also see list of precautions and interactions.


No special storage conditions required.


What is it used for?

  • Mebendazole is used to treat a number of problems.
  • It is used to treat infestations of the gut (intestine) by parasitic 'worms' (helminths).
  • In general this drug is used to treat a wide range of worm infections of the gut, but particularly infestations with threadworms (sometimes called pinworms). It is also used to treat infestation of the gut with roundworm, whipworm and hookworm.
  • Benefits of being on this drug can include eradication of helminth infestation of the gut.

Listed below are the typical uses of mebendazole.

  • Treatment of infections caused by Enterobius vermicularis (threadworm/pinworm)
  • Treatment of infections caused by Oxyuris vermicularis (a type of worm related to the threadworm)
  • Treatment of infections caused by Trichuris trichuria (whipworm)
  • Treatment of infections caused by Ascaris lumbricoides (large roundworm)
  • Treatment of infections caused by Ancylostoma duodenale (common hookworm)
  • Treatment of infections caused by Necator americanus (American hookworm)

On occasion your doctor may prescribe this medicine to treat a condition not on the above list.


How often do I take it?

  • Take this medication by mouth, with dose dependent on the type of worm (helminth). It is available as chewable tablets, or powder to suspend in water, and taken by mouth.
  • Use this medication for the duration of the prescription in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told not to by your doctor.
  • It may take some time before the full benefit of this drug takes effect.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • None known. Consult your doctor or pharmacist for more details.

When can I stop?

  • Always complete the full course as prescribed by your doctor.


If any of these persist or you consider them severe then inform your doctor or pharmacist.

Tell your doctor immediately if you develop any of the following symptoms: blistering of the skin, mouth, eyes and genitals, or fits (convulsions) in infants.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking mebendazole, tell your doctor or pharmacist if you are allergic to it; or to other anthelmintics; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist in case of: pregnancy.

Before using this medication tell your doctor or pharmacist your medical history, especially any of the following: none known.

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • It is not known whether drinking alcohol affects this drug's action.

The elderly: mebendazole can be used in the elderly.

Pregnancy and breastfeeding - please ensure you read the detailed information below


Mebendazole is not safe to take if you are, or are planning to become, pregnant.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Mebendazole is not safe to take if you are breastfeeding.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious, possibly fatal interactions may occur:

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

This information does not contain all possible interactions. Therefore, before using mebendazole, tell your doctor or pharmacist of all the products you use.


Taking too much mebendazole may cause the following: stomachcramps, feeling sick (nausea), vomiting and diarrhoea.

People who have taken too much mebendazole should seek assistance from a healthcare professional.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of mebendazole or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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