Emverm (Mebendazole) - Oral

What Is Emverm?

Emverm (mebendazole) is an oral prescription drug used to treat pinworm and other parasitic worm infections in people 2 years and older.

It belongs to a class of medications called anthelmintics or antiparasitic drugs. Emverm works by interfering with the reproduction and survival of the worms that cause infection.

It is available as a chewable tablet.

Drug Facts

Generic Name: Mebendazole

Brand Name(s): Emverm

Drug Availability: Prescription

Administration Route: Oral

Therapeutic Classification: Anthelmintic

Available Generically: No

Controlled Substance: N/A

Active Ingredient: Mebendazole

Dosage Form(s): Chewable tablet

What Is Emverm Used For?

The Food and Drug Administration (FDA) approved Emverm to treat individuals 2 years and older with gastrointestinal infections caused by the following worms:

  • Ancylostoma duodenale (hookworm)
  • Ascaris lumbricoides (roundworm)
  • Enterobius vermicularis (pinworm)
  • Necator americanus (hookworm)
  • Trichuris trichiura (whipworm)

How to Take Emverm

If you are prescribed Emverm, read the medication label and information leaflet that comes with your prescription. Talk to your healthcare provider about how to take your medication. Then, use it exactly as prescribed.

You must finish the full course of treatment prescribed, even if you feel better before you finish your pills. Stopping the medication too soon can increase the chances of becoming resistant to the antibiotic.

Depending on your infection, you will likely take Emverm for one or three days. However, it can take up to three weeks for the infection to completely clear up. If you aren't better after this time, contact your healthcare provider. Also, because pinworm infections can easily spread, your family members may need treatment too. Your healthcare provider will tell you how to disinfect your house and wash clothing, towels, and bedding.

When taking Emverm, chew or swallow the tablet whole. You can also crush it and mix it with food. It can be taken with or without food.

Talk to your healthcare provider if you have any questions or concerns.

Storage

Store at room temperature (between 68 F and 77 F), away from heat, direct light, and moisture. Do not store it in the bathroom. Keep this medication in its original labeled container and out of reach of children and pets. Keep the bottle tightly closed when not in use.

Off-Label Uses

Emverm is sometimes used off-label for indications that are not FDA-approved.

Healthcare providers may prescribe Emverm to treat:

  • Cystic echinococcosis (hydatid cyst disease), a tapeworm infection
  • Alveolar echinococcosis, a tapeworm infection
  • Capillariasis, a parasitic worm disease
  • Toxocariasis (visceral larva migrans), a roundworm infection
  • Trichinosis, a roundworm infection usually caused by raw or undercooked infected meat

How Long Does Emverm Take to Work?

Emverm is taken in one dose for pinworm or for three days for other types of worm infections. However, it may take up to three weeks until the infection is completely clear. If the infection is not clear in three weeks, consult your healthcare provider. You may need another course of treatment.

What Are the Side Effects of Emverm?

This is not a complete list of side effects, and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your pharmacist or a healthcare provider. You may report side effects to the FDA at fda.gov/medwatch or 1-800-FDA-1088.

Common Side Effects

Like other medications, Emverm can cause side effects. Tell your healthcare provider about any side effects you experience while taking this medication.

The most common side effects of Emverm are:

  • Stomach pain
  • Diarrhea
  • Rash
  • Flatulence (gas)
  • Nausea or vomiting
  • Loss of appetite

Severe Side Effects

Contact your healthcare provider immediately if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:

Allergic reactions are rare. However, get emergency medical help if you have hives, difficulty breathing, or swelling of the face, lips, tongue, or throat.

Long-Term Side Effects

While many people tolerate Emverm well, long-term or delayed side effects are possible. However, some long-term side effects can be mild, such as:

  • Appetite loss
  • Hair loss

Moderate long-term side effects can include: 

  • Increased liver enzymes
  • Liver problems 
  • Neutropenia (low neutrophils, a type of white blood cell)

Severe long-term side effects may include: 

  • Agranulocytosis (a life-threatening blood disorder caused by low neutrophil counts)
  • Seizures 
  • Stevens-Johnson syndrome
  • Toxic epidermal necrolysis
  • Glomerulonephritis (inflammation and damage to the kidneys)

Report Side Effects

Emverm may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your healthcare provider may send a report to the FDA's MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

Dosage: How Much Emverm Should I Take?

Drug Content Provided and Reviewed by IBM Micromedex®

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (Emverm™ chewable tablets):
    • For common roundworms, hookworms, and whipworms:
      • Adults and children 2 years of age and older—100 milligrams (mg) two times a day, morning and evening, for 3 consecutive days. Treatment may need to be repeated in 3 weeks.
      • Children younger than 2 years of age—Use and dose must be determined by your doctor.
    • For pinworms:
      • Adults and children 2 years of age and older—100 milligrams (mg) once a day for 1 day. Treatment may need to be repeated in 3 weeks.
      • Children younger than 2 years of age—Use and dose must be determined by your doctor.
  • For oral dosage form (Vermox™ chewable tablets):
    • For roundworms and whipworms:
      • Adults and children 1 year of age and older—500 milligrams (mg) once a day for 1 day.
      • Children younger than 1 year of age—Use and dose must be determined by your doctor.

Modifications

Emverm is only approved in adults and children 2 years and older. Seizures have occurred in children younger than 1 taking mebendazole.

There is not enough data suggesting that Emverm is harmful to take while pregnant. Still, talk to your healthcare provider if you are pregnant or plan to become pregnant while on Emverm.

Similarly, there is not enough information on the effects of Emverm on breastfeeding. Talk to your healthcare provider about whether you should stop breastfeeding while taking this medication.

Missed Dose

If you are taking Emverm for pinworm, you will just take one dose.

However, if you are taking Emverm for another type of worm infection, you will need to take it for three days. If you miss a dose of Emverm, take it as soon as you remember. If it is almost time for the next dose, skip the missed dose. Do not take two doses together. Contact your healthcare provider if you miss more than one dose of Emverm.

Overdose: What Happens If I Take Too Much Emverm?

An accidental Emverm overdose can cause stomach problems such as cramps, nausea, vomiting, and diarrhea.

Taking high dosages over longer periods can cause the following symptoms:

  • Hair loss
  • Liver enzyme changes
  • Liver problems
  • Low neutrophil counts
  • Kidney damage

What Happens If I Overdose on Emverm?


If you think you or someone else may have overdosed on Emverm, call a healthcare provider or the Poison Control Center (800-222-1222).

If someone collapses or isn't breathing after taking Emverm, call 911 immediately.

Precautions

Drug Content Provided and Reviewed by IBM Micromedex®

It is important that your doctor check your progress at regular visits, especially in infections in which high doses are needed. This is to make sure that the infection is cleared up completely, and to allow your doctor to check for any unwanted effects. Blood tests may be needed.

If your symptoms do not improve after you have taken this medicine for the full course of treatment, or if they become worse, check with your doctor.

Mebendazole can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.

It is important to tell your doctor if you are pregnant before taking this medicine.

For patients taking mebendazole for pinworms:

  • Pinworms may be easily passed from one person to another, especially among persons in the same household. Therefore, all household members may have to be treated at the same time to prevent infection or reinfection.
  • Some doctors may also recommend other measures to help keep your infection from returning. If you have any questions about this, check with your doctor.

For patients taking mebendazole for hookworms or whipworms:

  • In hookworm and whipworm infections, anemia may occur. Therefore, your doctor may want you to take iron supplements to help clear up the anemia.
  • It is important to take iron every day during treatment and for 6 months after you stop taking mebendazole. Do not miss any doses. If you have any questions about this, check with your doctor.

In some patients, infections may return after treatment with mebendazole. To help prevent the infection from coming back:

  • Wash hands and fingernails often, especially before eating and after using the toilet.
  • Wash all fruits and vegetables thoroughly. Cook them well.
  • Clean the bedroom floor by vacuuming or damp mopping for several days after treatment with this medicine. Avoid dry sweeping that may stir up the dust.
  • Wash (not shake) all beddings and nightclothes (pajamas).
  • Wear tight underpants both day and night. Change them daily. Also, wear shoes.
  • Use the bathroom and keep the toilet seats clean.

This medicine may cause serious skin reactions when taken together with metronidazole. Check with your doctor right away if you have blistering, peeling, or loose skin, red skin lesions, severe acne or skin rash, sores or ulcers on the skin, or fever or chills while you are using this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

What Are Reasons I Shouldn’t Take Emverm?

Emverm is not appropriate for everyone. You should not take this medication if you are allergic to mebendazole or any inactive ingredients in Emverm or if you take another medication called Flagyl (metronidazole). Combining Flagyl with Emverm could cause serious, life-threatening skin reactions.

What Other Medications Interact With Emverm?

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter (OTC) medicines and vitamins or supplements.

The most notable drug interaction is with Flagyl. People taking Flagyl should not take Emverm. The combination may cause serious, life-threatening skin reactions.

Examples of other medicines that may interact with Emverm include:

What Medications Are Similar?

Emverm is used to treat various worm infections, including pinworm, roundworm, hookworm, and whipworm.

Other medications used to treat various worm infections include:

  • Albenza (albendazole) prescription oral tablets 
  • Pyrantel pamoate OTC oral suspension can be used to treat pinworm. 
  • Stromectol (ivermectin) prescription oral tablets

This is a list of drugs also used for worm infections. It is NOT a list of drugs recommended to take with Emverm. Talk to your pharmacist or a healthcare provider if you have questions.

Frequently Asked Questions

  • What is Emverm used for?

    Emverm is used in adults and children 2 years and older to treat pinworm or other types of intestinal worm infections, including certain types of hookworm, roundworm, or whipworm.

  • How does Emverm work?

    Emverm works by interfering with the reproduction and survival of the worms causing your infection.

  • What drugs should not be taken with Emverm?

    Flagyl (metronidazole) should never be taken with Emverm. Metronidazole is an antibiotic used to treat various types of infections.

    The combination of these two drugs can cause a serious or life-threatening skin reaction. Other drugs that may interact with Emverm include phenobarbital, phenytoin, carbamazepine, and cimetidine. Review your medication list with your healthcare provider before taking Emverm.

  • What are the side effects of Emverm?

    The most common side effects of Emverm are stomach pain, diarrhea, appetite loss, gas, nausea, and vomiting.

    Serious side effects may include seizures and swelling under the skin. Get emergency medical help if you have hives, difficulty breathing, or swelling around the face.

  • How do I stop taking Emverm?

    Your healthcare provider will advise you on how long to take Emverm, usually one dose for pinworm or three days for other types of worm infection. However, finish the full course of treatment, and do not stop taking Emverm early. It may take up to three weeks for the infection to clear completely. If symptoms are not gone at this point, contact your healthcare provider. You may need a second course of treatment.

How Can I Stay Healthy While Taking Emverm?

Before taking Emverm, discuss your medical history and all medications you take with your healthcare provider.

Follow your healthcare provider’s instructions on how and when to take Emverm. Read the patient information leaflet that comes with your prescription, and be sure to talk to your healthcare provider if you have questions. Ask your healthcare provider if the other people in your household should be treated.

Although Emverm can treat a variety of worm infections, pinworm is the most common worm infection seen in the United States. Pinworm can only be transferred by humans. The eggs can survive indoors for up to three weeks. Pinworm is more likely to occur in children under 18, caregivers of infected children, and people who are institutionalized.

The following tips can help prevent the spread of pinworm infection:

  • Wash hands, including nails, frequently and carefully, especially after using the restroom, handling diapers, and before preparing or eating food. Make sure your child washes their hands often and carefully as well. 
  • Shower frequently.
  • Keep fingernails short. Do not bite your nails. Use a nail brush and sanitize after use. Use a different nail brush for each family member.
  • Discourage children from scratching their bottoms. If you see them scratching, have them wash their hands. 
  • Wear tight-fitting undergarments. Change and wash clothing, towels, and bed sheets every day. Do not shake out towels and bed sheets. 
  • Vacuum or mop the bedroom floor. Avoid dry sweeping. 
  • Disinfect shared surfaces such as doorknobs, toilet seats, countertops, phones, and remotes. Eggs can live for up to three weeks on these indoor surfaces.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended to replace medical advice, diagnosis, or treatment from a healthcare provider. Consult your healthcare provider before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Dailymed. Emverm label.

  2. PubChem. Mebendazole.

  3. Prescribers' Digital Reference. Mebendazole - drug summary.

  4. Chai JY, Jung BK, Hong SJ. Albendazole and mebendazole as anti-parasitic and anti-cancer agents: an update. Korean J Parasitol. 2021;59(3):189-225. doi:10.3347/kjp.2021.59.3.189

  5. Chen KT, Twu SJ, Chang HJ, Lin RS. Outbreak of Stevens-Johnson syndrome/toxic epidermal necrolysis associated with mebendazole and metronidazole use among Filipino laborers in Taiwan. Am J Public Health. 2003;93(3):489-492. doi:10.2105/ajph.93.3.489

  6. Centers for Disease Control and Prevention. Epidemiology & risk factors.

  7. Centers for Disease Control and Prevention. Pinworm infection FAQs.

  8. MedlinePlus. Pinworms.

By Karen Berger, PharmD
Karen Berger, PharmD, is a community pharmacist and medical writer/reviewer.