Zithromax (azithromycin) is a prescription drug used to treat infections of the ears, lungs, skin, and throat, bronchitis, pneumonia and some sexually transmitted diseases. This drug is available in the form of oral suspension and liquid. The liquid form should be taken with the help of a special measuring device. How long you will need to take Zithromax for depends on the condition you are being treated for. The usual period of treatment may vary from 1 to 5 days. Make sure you take this drug regularly even if you start to feel better. Feeling better does not necessarily mean the growth of bacteria has been stopped. If you are allergic to the active ingredient this medicine contains (azithromycin), make sure you do not start taking Zithromax without previously discussing this with your doctor. Any other medications you are taking at the moment are supposed to be reported to your health care provider, especially medications that suppress the immune system, terfenadine, digoxin, ergotamine, dihydroergotamine, phenytoin, anticoagulants, nelfinavir, and cyclosporine. Interactions have been reported between the medications mentioned and Zithromax. Your health care provider also needs to know as much as possible about your current health conditions and any medical conditions you have been diagnosed with. The following medical conditions are especially important to mention: liver disease, myasthenia gravis, kidney disease, heart rhythm disorder, and a history of Long QT syndrome. Side effects of Zithromax are not numerous and tend to go away on their own. The following mild side effects are sometimes possible: ringing in your ears, skin rash, stomach upset, mild nausea, diarrhea, stomach pain, dizziness, constipation, headache, mild itching, insomnia, nervous feeling, vomiting, and decreased sense of taste. Just like most antibiotics Zithromax can make your skin more sensitive to sunlight. Make sure you avoid staying outside for a log time to prevent a sun burn. More serious side effects are also possible and may include swelling, trouble swallowing, severe skin rash, irregular heartbeat, itching, yellowing of the skin or eyes, hoarseness, difficulty breathing, and hives. An overdose of Zithromax is possible if you are not careful with the dose you have been prescribed and too much of this drug. The following symptoms may indicate an overdose: vomiting, stomach discomfort, nausea, and diarrhea. If you get any of the symptoms mentioned, seek emergency medical help to make sure your treatment is both safe and efficient. Never share your dose of Zithromax with other people to whom it was not prescribed, as they may have some contraindications you are not aware of. Store this drug in some place where it will not be accessed by children. It's important to keep on taking this medicine for as long as prescribed as you may feel better before the infection has been treated completely. Talk to your doctor if you have any questions or concerns.