AZITHROMYCIN
The prescription antibiotic azithromycin treats a number of bacterial infections, including bronchitis, pneumonia, sexually transmitted diseases, and infections of the ears, throat, and skin. It is a so-called depot antibiotic, which means it is stored in a deposit in bodily tissues and released slowly—thus it can be taken for three days and will then continue to work for another week.
CHEMICAL NAME
Azithromycin dihydrate; azithromycin is in a class of drugs called macrolide antibiotics.
MEDICINES
Azithromycin is often present in medicines as azithromycin monohydrate or azithromycin dihydrate. It is sold under the names Zithromax and Zmax and as generic azithromycin.
HOW IT WORKS
Like other macrolides, azithromycin inhibits bacterial protein synthesis, either killing the bacteria or preventing their growth. Because of its long half-life, it can be taken once a day for shorter durations than other macrolides.
SIDE EFFECTS
Common side effects include diarrhea, nausea, and vomiting. In general: Azithromycin is stored in the tissues and continues to work for up to 10 days. The problem: As is the case with all antibiotics, side effects can be serious. Normally a doctor responds to this situation by halting medication with the problem substance. But because of azithromycin’s extended release, that approach does not work with this drug. A physician should be consulted immediately if there are symptoms of heart rhythm problems.
INTERACTIONS
Azithromycin should not be taken with ergot alkaloids (for migraines), astemizole (an antihistamine), and alfentanil (a synthetic opioid) because the combination raises the risk of side effects, including toxicity. Azithromycin also increases the effect of digoxin (used to treat cardiac conditions like heart failure).
PROPER USE
Azithromycin is taken on an empty stomach one hour before or two hours after a meal. Adults take between 500 and 2,000 mg per day as an initial single dose. This is followed with doses of 250 to 500 mg once a day for several days.