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Some commonly used brand names are:

In the U.S.—

  • Hetrazan

In Canada—

  • Hetrazan

Generic name product may be available in the U.S.


  • Anthelmintic, systemic


Diethylcarbamazine (dye-eth-il-kar-BAM-a-zeen) is used in the treatment of certain worm infections. This medicine works by killing the worms. It is used to treat:

  • Bancroft's filariasis;
  • Eosinophilic lung (tropical pulmonary eosinophilia; tropical eosinophilia);
  • Loiasis; and
  • River blindness (onchocerciasis).

It will not work for other kinds of worm infections (for example, pinworms or tapeworms).

Diethylcarbamazine is available only with your doctor's prescription, in the following dosage form:

  • Oral
  • Tablets (U.S. and Canada)

Before Using This Medicine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For diethylcarbamazine, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to diethylcarbamazine. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Treatment of pregnant patients with diethylcarbamazine should be delayed until after delivery. However, diethylcarbamazine has not been shown to cause birth defects or other problems in humans.

Breast-feeding—It is not known whether diethylcarbamazine passes into breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.

Children—Although there is no specific information comparing use of diethylcarbamazine in children with use in other age groups, this medicine is not expected to cause different side effects or problems in children than it does in adults.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of diethylcarbamazine in the elderly with use in other age groups.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your health care professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.

Proper Use of This Medicine

Diethylcarbamazine should be taken immediately after meals.

To help clear up your infection completely, keep taking this medicine for the full time of treatment , even if your symptoms begin to clear up after a few days. In some patients, a second course of this medicine may be required to clear up the infection completely. If you stop taking this medicine too soon, your infection may return. Do not miss any doses .

Dosing—The dose of diethylcarbamazine 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 diethylcarbamazine. If your dose is different, do not change it unless your doctor tells you to do so.

The number of tablets 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 taking diethylcarbamazine .

  • For oral dosage form (tablets):
    • For Bancroft's filariasis, loiasis, and river blindness:
      • Adults—Dose is based on body weight and must be determined by your doctor. The usual dose is 2 to 3 milligrams (mg) per kilogram (kg) (0.9 to 1.3 mg per pound) of body weight three times a day.
      • Children—Use and dose must be determined by your doctor.
    • For eosinophilic lung:
      • Adults—Dose is based on body weight and must be determined by your doctor. The usual dose is 6 mg per kg (2.7 mg per pound) of body weight a day. This is taken for four to seven days.
      • Children—Use and dose must be determined by your doctor.

Missed dose—If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—To store this medicine:

  • Keep out of the reach of children.
  • Store away from heat and direct light.
  • Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
  • Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

Precautions While Using This Medicine

If your symptoms do not improve within a few days, or if they become worse, check with your doctor.

For patients taking diethylcarbamazine for river blindness :

  • It is important that your doctor check your progress at regular visits. This is to help make sure that the infection is cleared up completely. Also, your doctor may want you to have your eyes checked by an ophthalmologist (eye doctor).
  • Diethylcarbamazine may cause loss of vision, night blindness, or tunnel vision with prolonged use. This medicine may also cause some people to become dizzy. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or are not alert or able to see well . If these reactions are especially bothersome, check with your doctor.
  • Doctors may also prescribe a corticosteroid (a cortisone-like medicine) for certain patients with river blindness, especially those with severe symptoms. This is to help reduce the inflammation caused by the death of the worms. If your doctor prescribes these two medicines together, it is important to take the corticosteroid along with diethylcarbamazine. Take them exactly as directed by your doctor. Do not miss any doses.

Side Effects of This Medicine

Along with its needed effects, a medicine 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:

More common

Itching and swelling of face, especially eyes

Less common

Fever; painful and tender glands in neck, armpits, or groin; skin rash

Additional side effects may occur if you use this medicine for a long time in the treatment of river blindness. Check with your doctor as soon as possible if any of the following side effects occur:

Loss of vision; night blindness; tunnel vision

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

More common

Headache; joint pain; unusual tiredness or weakness

Less common

Dizziness; nausea or vomiting

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Revised: 8/11/1995

Further information

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