A Z-Pak is a prepackaged form of the antibiotic azithromycin, sold under the brand name Zithromax. Like other antibiotics, a Z-Pak treats bacterial infections. Zithromax will not cure or shorten the duration of a viral infection. You should never take antibiotics prescribed for another person, and take a Z-Pak only if your doctor recommends it.
Your doctor may prescribe a Z-Pak to treat bacterial sinusitis, bacterial exacerbations of chronic obstructive pulmonary disease, certain community-acquired pneumonias, pharyngitis or tonsillitis caused by streptococcus pyogenes bacteria, streptococcal or staph aureus skin infections or childhood ear infections. Some genital infections also respond to Zithromax; they include cervicitis and urethritis caused by Chlamydia trachomatis or Neisseria gonorrhoeae and genital ulcer disease, but they dot include syphilis.
Patients often pressure doctors into unnecessarily prescribing Z-Paks for upper respiratory infections, although many are caused by viruses, not bacteria, according to an editorial published in the April 2007 "Journal of Family Practice." Azithromycin, like other antibiotics, can have side effects including allergic reactions, diarrhea, nausea or abdominal pain. Zithromax has also been associated with a small increase in the risk of cardiovascular death in some patients, the Food and Drug Administration warns.