Vermox Side Effects

Generic name: mebendazole

Medically reviewed by Drugs.com. Last updated on Jun 2, 2025.

Note: This document provides detailed information about Vermox Side Effects associated with mebendazole. Some dosage forms listed on this page may not apply specifically to the brand name Vermox.

Applies to mebendazole: oral tablet chewable.

Precautions

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 (the active ingredient contained in Vermox) 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.

Serious side effects of Vermox

Along with its needed effects, mebendazole may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking mebendazole:

Other side effects of Vermox

Some side effects of mebendazole may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

See also:

For healthcare professionals

Applies to mebendazole: compounding powder, oral tablet chewable.

General adverse events

At the recommended dose, this drug was generally well tolerated; however, patients with high parasitic burdens reported diarrhea and abdominal pain.^[Ref]

Gastrointestinal

• Common (1% to 10%): Abdominal pain
• Uncommon (0.1% to 1%): Abdominal discomfort, diarrhea, flatulence
• Frequency not reported: Nausea, vomiting^[Ref]

Dermatologic

• Rare (0.01% to 0.1%): Rash
• Frequency not reported: Pruritus
• Postmarketing reports: Toxic epidermal necrolysis, Stevens-Johnson syndrome, exanthema, alopecia, angioedema, urticaria^[Ref]

Metabolic

• Frequency not reported: Anorexia^[Ref]

Hepatic

• Frequency not reported: Transient changes in liver function tests, granulomatous hepatitis
• Postmarketing reports: Hepatitis, abnormal liver function tests^[Ref]

Hematologic

• Frequency not reported: Profound leukopenia, anemia, thrombocytopenia, pancytopenia
• Postmarketing reports: Agranulocytosis, neutropenia^[Ref]

Nervous system

• Frequency not reported: Weakness, drowsiness
• Postmarketing reports: Convulsions/seizures, dizziness^[Ref]

Renal

• Postmarketing reports: Glomerulonephritis^[Ref]

Other

• Frequency not reported: Chills, drug fever, flushing^[Ref]

Hypersensitivity

• Postmarketing reports: Hypersensitivity (including anaphylactic reaction, anaphylactoid reaction)^[Ref]

Further information

Vermox side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer