Azithromycin

Azithromycin is an antibiotic prescribed to patients with cystic fibrosis (CF) who develop respiratory infections. CF is an inherited, life-threatening disease caused by a defect in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which results in the abnormal function of organs such as the lungs and pancreas, excessive production of thick and sticky mucus, as well as a higher propensity to develop respiratory infections.

The antibiotic is currently commercialized in the United States under the brand names Zithromax and Zmax, and it comes in the form of a tablet, an extended-release long-acting liquid, and a liquid taken orally. Depending on the purpose of the treatment, azithromycin may be take once a day or once a week, according to a physician’s treatment plan.

History of Azithromycin

Pfizer currently commercializes azithromycin in the United States, after the first approval of the product by the end of the 1990s. Backed by clinical trials that confirmed  that prophylaxis with once-weekly Zithromax reduced the risk of developing Mycobacterium avium complex (MAC) bacteria in the bloodstream and the clinical signs and symptoms associated with it, the U.S. Food and Drug Administration (FDA) approved the commercialization of the antibiotic in 1996. Zithromax TRI-PAK (azithromycin) tablets reached the market in 2002, and Zmax (azithromycin) Extended Release Oral Suspension in 2005.

AzithromycinHow Azithromycin Works

Azithromycin is included in a class of medications known as macrolide antibiotics, and it functions by attacking the bacteria present in the body and blocking its growth. It has been demonstrated effective in treating bacterial infections, including bronchitis, pneumonia, sexually transmitted diseases, as well as infections of the ears, lungs, sinuses, skin, throat, and reproductive organs. In addition, the antibiotic is also prescribed for either prevention or treatment of disseminated MAC infection, which is a common lung infection among patients with human immunodeficiency virus (HIV).

Other Details About Azithromycin

All medications have potential side effects, but in the case of azithromycin, the FDA issued a special recommendation warning about its dangers. “The U.S. Food and Drug Administration (FDA) is warning the public that azithromycin (Zithromax or Zmax) can cause abnormal changes in the electrical activity of the heart that may lead to a potentially fatal irregular heart rhythm. Patients at particular risk for developing this condition include those with known risk factors such as existing QT interval prolongation, low blood levels of potassium or magnesium, a slower than normal heart rate, or use of certain drugs used to treat abnormal heart rhythms, or arrhythmias,” stated the FDA in 2013.

Note: Cystic Fibrosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.

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