In the U.S.—

In Canada—

• Antibacterial, systemic

Azithromycin (az-ith-roe-MYE-sin) is used to treat bacterial infections in many different parts of the body. It is also used to prevent Mycobacterium avium complex (MAC) disease in patients infected with the human immunodeficiency virus (HIV). It works by killing bacteria or preventing their growth. However, this medicine will not work for colds, flu, or other viral infections. Azithromycin may be used for other problems as determined by your doctor.

Azithromycin is available only with your doctor's prescription, in the following dosage forms:

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

Parenteral
• Injection (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 azithromycin, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to azithromycin 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—Azithromycin has not been studied in pregnant women. However, azithromycin has not been shown to cause birth defects or other problems in animal studies.

Breast-feeding—It is not known whether azithromycin 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—This medicine has been tested in a limited number of children up to the age of 16. In effective doses, the medicine has not been shown to cause different side effects or problems than it does in adults.

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. When you are taking azithromycin, it is especially important that your health care professional know if you are taking any of the following:

• Antacids, aluminum- and magnesium-containing—Antacids may decrease the amount of azithromycin in the blood, which may decrease its effects. To avoid problems, azithromycin should be taken at least 1 hour before or at least 2 hours after antacids

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

Azithromycin capsules and pediatric oral suspension should be taken at least 1 hour before or at least 2 hours after meals. Azithromycin tablets and adult single dose oral suspension may be taken with or without food.

To help clear up your infection completely, keep taking azithromycin 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.

Dosing—

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

The number of capsules or tablets or the amount of suspension that you take depends on the medical problem for which you are taking azithromycin.

• For the oral suspension dosage form:
  • For chancroid in men and chlamydia infections:
    • Adults and adolescents—1 gram taken once as a single dose.
    • Children 6 months to 12 years of age—Use and dose must be determined by your doctor.
  • For gonococcal infections:
    • Adults and adolescents—2 grams taken once as a single dose.
    • Children 6 months to 12 years of age—Use and dose must be determined by your doctor.
  • For otitis media and pneumonia:
    • Children 6 months to 12 years of age—10 milligrams (mg) per kilogram (kg) (4.5 mg per pound) of body weight once a day on the first day, then 5 mg per kg (2.2 mg per pound) of body weight once a day on days two through five.
  • For strep throat:
    • Adults and adolescents—The oral suspension is usually not used. Refer to azithromycin capsules or tablets.
    • Children 2 to 12 years of age—12 mg per kg (5.4 mg per pound) of body weight once a day for five days.
    • Children up to 2 years of age—Use and dose must be determined by your doctor.

• For the tablet dosage form:
  • For bronchitis, strep throat, pneumonia, and skin infections:
    • Adults and adolescents 16 years of age and older—500 milligrams (mg) on the first day, then 250 mg once a day on days two through five.
    • Children up to 16 years of age—Use and dose must be determined by your doctor.
  • For chlamydia infections:
    • Adults and adolescents 16 years of age and older—1000 mg taken once as a single dose.
    • Children up to 16 years of age—Use and dose must be determined by your doctor.
  • For prevention of Mycobacterium avium complex (MAC) disease:
    • Adults and adolescents 16 years of age and older—1200 mg once a week.
    • Children up to 16 years of age—Use and dose must be determined by your doctor.
  • For sinusitis:
    • Adults and adolescents— 500 mg a day for 3 days
    • Children up to 16 years of age—Use and dose must be determined by your doctor.

• For injection dosage form:
  • For pelvic inflammatory disease:
    • Adults and adolescents 16 years of age and older—500 milligrams (mg) once a day for one or two days, injected into a vein.
    • Children up to 16 years of age—Use and dose must be determined by your doctor.
  • For pneumonia:
    • Adults and adolescents 16 years of age and older—500 mg once a day for at least two days, injected into a vein.
    • Children up to 16 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.
• Store the pediatric suspension form of azithromycin in the refrigerator.
• 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.

Stop taking this medicine and get emergency help immediately if any of the following side effects occur :

• More common (for injection form only)
  • Pain, redness, and swelling at site of injection 
  
  

• Rare
  • Abdominal or stomach cramps or pain (severe);  abdominal tenderness;  diarrhea (watery and severe, which may be bloody);  difficulty in breathing;  fever;  joint pain;  skin rash;  swelling of face, mouth, neck, hands, and feet 
  
  

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 (mild);  nausea;  stomach pain or discomfort 
  
  

• Rare
  • Dizziness;  headache 
  
  

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

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, azithromycin is used in certain patients with the following medical condition:

• Trachoma (treatment)

Other than the above information, there is no additional information relating to proper use, precautions, or side effects for this use.