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Generic name: thiabendazole [ thye-a-BEN-da-zole ]
Brand name: Mintezol

Thiabendazole is used for:

Treating worm infections. It may also be used for other conditions as determined by your doctor.

Thiabendazole is an anthelmintic. The exact way thiabendazole works is unknown. It is thought to work by blocking egg and larva production. It may also block a certain enzyme needed by the parasite.

Do NOT use thiabendazole if:

  • you are allergic to any ingredient in thiabendazole

Contact your doctor or health care provider right away if any of these apply to you.

Before using thiabendazole:

Some medical conditions may interact with thiabendazole. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have liver or kidney problems
  • if you have anemia or improper nutrition or you are dehydrated

Some MEDICINES MAY INTERACT with thiabendazole. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Xanthine derivatives (eg, theophylline) because side effects, including risk of nausea, vomiting, heart problems, or seizures, may be increased by thiabendazole

This may not be a complete list of all interactions that may occur. Ask your health care provider if thiabendazole may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use thiabendazole:

Use thiabendazole as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take thiabendazole after meals.
  • Chew thoroughly before swallowing.
  • To clear up your infection completely, continue using thiabendazole for the full course of treatment even if you feel better in a few days.
  • If you miss a dose of thiabendazole, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use thiabendazole.

Important safety information:

  • Thiabendazole may cause drowsiness, dizziness, blurred vision, or lightheadedness. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to thiabendazole. Using thiabendazole alone, with certain other medicines, or with alcohol may lessen your ability to drive or perform other potentially dangerous tasks.
  • Strict hygiene is essential to prevent reinfection. To prevent getting this infection again, disinfect toilet facilities daily and change and wash underwear, bed linens, towels, and pajamas daily.
  • Pinworm infections are easily spread to others. If one family member has a pinworm infection, all family members in close contact with the patient should be treated. This decreases the chance of spreading the infection.
  • Do not use thiabendazole to prevent worm infestations.
  • Thiabendazole may cause high blood sugar (eg, thirst, increased urination, confusion, drowsiness, flushing, rapid breathing, fruity breath odor). If these symptoms occur, tell your doctor immediately.
  • LAB TESTS, including liver function tests, may be performed to monitor your progress. Be sure to keep all doctor and lab appointments.
  • Use thiabendazole with caution in the ELDERLY because they may be more sensitive to its effects.
  • Use thiabendazole with extreme caution in CHILDREN younger than 4 years of age or who weigh less than 30 pounds (13.6 kg). Safety and effectiveness in these age and weight groups have not been established.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, discuss with your doctor the benefits and risks of using thiabendazole during pregnancy. It is unknown if thiabendazole is excreted in breast milk. Do not breast-feed while taking thiabendazole.

Possible side effects of thiabendazole:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Appetite loss; bad urine odor; diarrhea; dizziness; drowsiness; dry eyes; giddiness; headache; indigestion; irritability; nausea; sensation of floating; stomach upset or pain; tiredness; vomiting; weakness; worms in mouth or nose.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); blood in urine; blurred vision; change in vision; chills; collapse; confusion; dark urine; depression; enlarged lymph nodes; flushing; hoarseness; increased thirst or urination; loss of coordination; numbness; red, swollen, or blistered skin; ringing in the ears; seizures; severe stomach pain; sore throat or fever; strange feeling in your eyes; uncontrolled urination; vision tinged yellow; yellowing of the skin or eyes.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include changes in vision or personality; mental/mood changes.

Proper storage of thiabendazole:

Store thiabendazole at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep thiabendazole out of the reach of children and away from pets.

General information:

  • If you have any questions about thiabendazole, please talk with your doctor, pharmacist, or other health care provider.
  • Thiabendazole is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information is a summary only. It does not contain all information about thiabendazole. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.

Issue Date: June 3, 2015

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.