In the U.S.—

• Antibacterial, systemic

Dirithromycin (dye-RITH-roe-mye-sin) is used to treat bacterial infections in many different parts of the body. It works by killing bacteria or preventing their growth. However, this medicine will not work for colds, flu, or other virus infections.

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

Oral
• Tablets (U.S.)

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 dirithromycin, the following should be considered:

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

Pregnancy—Dirithromycin has not been studied in pregnant women. However, studies in animals have shown that dirithromycin causes birth defects and other problems at high doses. Before taking this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.

Breast-feeding—It is not known whether dirithromycin 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—Studies on this medicine have been only in adult patients, and there is no specific information comparing use of dirithromycin in children with use in other age groups.

Older adults—This medicine has been tested in a limited number of elderly patients and has not been shown to cause different side effects or problems in older people than it does in younger adults.

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.

• Liver disease—Patients with moderate to severe liver disease may have an increased chance of side effects

Dirithromycin should be taken with food or within 1 hour after eating.

To help clear up your infection completely, keep taking dirithromycin for the full time of treatment, even if you begin to feel better after a few days. If you stop taking this medicine too soon, your symptoms may return.

Do not cut, crush, or chew dirithromycin tablets.

Dosing—

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

• For oral dosage form (tablets):
  • For bacterial infections:
    • Adults and teenagers—500 milligrams (mg) once a day for seven to fourteen days.
    • Children up to 12 years of age—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.

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

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 as soon as possible if any of the following side effects occur:

• Rare
  • Abdominal tenderness;  fever;  severe abdominal or stomach cramps and pain;  watery and severe diarrhea, which may also be bloody 
  
  

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:

• Less common
  • Diarrhea;  dizziness;  headache;  nausea;  vomiting ;  weakness 
  
  

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