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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Generic drug name: mebendazole (meb EN dah zoll)
Brand name(s): VERMOX
GENERIC: not available FAMILY: Drugs for Parasitic infection
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

Mebendazole caused malformations and death in developing fetuses in animal studies. Because of the potential for serious adverse effects to the fetus, this drug should not be used by pregnant women.

Breast-feeding Warning

No information is available from either human or animal studies. However, it is likely that this drug, like many others, is excreted in human milk. If you need to take mebendazole for several weeks, as opposed to a few days, you should consult with your doctor if you are planning to nurse.

Facts About This Drug [top]

Mebendazole is approved by the FDA for treatment of pinworm, whipworm, roundworm, and hookworm.[1] The independent source of drug information for health professionals, The Medical Letter on Drugs and Therapeutics, lists mebendazole as the drug of choice for pinworm, whipworm, roundworm, and hookworm.[2]

It is very important that these conditions be treated, since if worms escape from the intestines, they can be quite disturbing under the skin, and dangerous in the heart, mouth, liver, or...

Mebendazole is approved by the FDA for treatment of pinworm, whipworm, roundworm, and hookworm.[1] The independent source of drug information for health professionals, The Medical Letter on Drugs and Therapeutics, lists mebendazole as the drug of choice for pinworm, whipworm, roundworm, and hookworm.[2]

It is very important that these conditions be treated, since if worms escape from the intestines, they can be quite disturbing under the skin, and dangerous in the heart, mouth, liver, or joints.[3],[4] Masses of roundworms have blocked the intestines or bile duct during therapy.[5] In high doses mebendazole has suppressed the bone marrow. Mebendazole is not approved in the United States for tapeworm or hydatid diseases. Effectiveness of mebendazole depends on whether the infestation is minor or severe, how long it takes worms to pass through your digestive tract, whether or not you have diarrhea, and the susceptibility of the worms. It may take a few days for the body to expel dead forms in the stool.

Length of therapy varies from three days to several months, according to the type and number of parasites. At times treatment needs to be repeated at least once. In severe infections, use of mebendazole may prevent the need for a blood transfusion or surgery. Compared to some other pinworm medicine, mebendazole has an advantage of not staining clothing or bedding.

You may be more susceptible to parasites if you take immunosuppressant drugs or corticosteroids.[4] Several measures can prevent infestation. Wear shoes. Do not go barefoot where human or animal feces may be on the ground, including beaches, children’s sandboxes, and fertilized gardens. Wash fruits and vegetables thoroughly. Eat meat that is completely cooked. Wash your hands before preparing food, eating, and after going to the toilet. Use sanitary conditions to dispose of human feces. Be cautious when traveling to areas with dense shade, high humidity, and sandy soil, coupled with poor sanitation.

Before You Use This Drug [top]

Tell your doctor if you have or have had:

  • pregnancy or are breast-feeding:
  • allergies to drugs
  • Crohn’s disease
  • inflammatory bowel disease
  • liver disease
  • ulcerative colitis

Tell your doctor of activities, places, or work that may have exposed you to parasites, especially if you have:

  • lived or traveled in tropical or subtropical areas, especially the southeastern United States, the Caribbean, Central and South America, the Philippines, Africa, Thailand, Vietnam, Burma, Turkey, and Eastern Europe
  • worked in agriculture, mining, plumbing, tunneling, or with foreign missions, immigrants, refugees, or foreign visitors
  • been duck hunting

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • If you plan to have any surgery, including dental, tell your doctor that you take this drug.
  • Check with your doctor if there is no improvement within a few days.
  • Have regular visits with your doctor to check on progress.
  • Check with your doctor as to whether you need iron supplements (for hookworms or whipworms).
  • After treatment, wash all bedding and nightclothes thoroughly to prevent reinfection.

How to Use This Drug [top]

  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Take with or without food. Check with your doctor to see whether you should take with a high-fat meal.
  • This medication can be broken, chewed, or crushed.
  • Capsules may be opened and the contents mixed with applesauce, jelly, or ketchup, then swallowed.
  • If on high-dose therapy, take with a fatty meal.
  • Take this drug for the prescribed length of time. If you stop too soon, your symptoms could come back.
  • Treat all household members at the same time (pinworms).
  • Store at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Keep out of reach of children.

Interactions with Other Drugs [top]

Evaluations of Drug Interactions 2003 lists no drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods as causing “highly clinically significant” or “clinically significant” interactions when used together with the drugs in this section. We also found no interactions in the drugs’ FDA-approved professional package inserts. However, as the number of new drugs approved for marketing increases and as more experience is gained with these drugs over time, new interactions may be discovered.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • fever
  • skin rash or itching
  • sore throat
  • unusual tiredness or weakness

Call your doctor if these symptoms continue:

  • abdominal pain or upset
  • diarrhea
  • dizziness
  • hair loss
  • headache
  • nausea or vomiting

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • complete blood count (if on high-dose therapy)
  • perianal exam (for pinworms)
  • stool exam

last reviewed April 30, 2021