Thiabendazole (By mouth)


Thiabendazole (thye-a-BEN-da-zole)

Treats infections caused by hookworms, roundworms, threadworms, pork worms (trichinosis), and other kinds of worms.

Brand Name(s)

There may be other brand names for this medicine.

When This Medicine Should Not Be Used

You should not use this medicine if you have had an allergic reaction to thiabendazole.

How to Use This Medicine

Chewable Tablet, Liquid

  • Your doctor will tell you how much medicine to take and how often.
  • Chew the chewable tablet well before swallowing.
  • It is best to take your medicine after a meal.
  • Shake the oral liquid bottle well before each use.
  • Measure your oral liquid dose carefully with a measuring spoon or medicine cup.

If a dose is missed:

  • Take the missed dose as soon as possible, unless it is almost time for your next dose.
  • Skip the missed does if it is almost time for your next regular dose.
  • You should not use two doses at the same time.

How to Store and Dispose of This Medicine

  • Store the medicine at room temperature, away from heat, moisture, and direct light. Do not freeze.
  • Keep all medicine out of the reach of children.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Make sure your doctor knows if you are taking theophylline.

Warnings While Using This Medicine

  • Talk with your doctor before taking thiabendazole if you have liver or kidney disease.
  • If you are pregnant or breastfeeding, talk to your doctor before taking this medicine.
  • This medicine may make you dizzy or drowsy. Avoid driving or using machinery.
  • This medicine may blur your vision or make everything you see look yellow (yellow vision). If you have questions about this, talk with your doctor.
  • This medicine treats worm infections but will not prevent worm infections.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Rash or hives
  • Red peeling skin
  • Fever or chills
  • Bloody urine or dark-colored urine
  • Seizures
  • Yellowing of eyes or skin

If you notice these less serious side effects, talk with your doctor:

  • Blurred vision, yellow vision
  • Feeling dizzy or drowsy
  • Headache
  • Nausea
  • Dry mouth, nose, or eyes
  • Bad odor of your urine
  • Ringing in your ears
  • Flushing (redness or warmth in your face)

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Version Info

  • Last Reviewed on 06/12/2013

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