What are the side effects of azithromycin?

It is important to tell your health professional about any medicines you may be taking, or if you have any current illness, allergies or long-term health conditions. This will help them decide if azithromycin is suitable for you.

Azithromycin can affect your heart rate, so you must tell your doctor if you have any heart problems (e.g. irregular heart beat or arrhythmia).

Side effects of azithromycin

(1 to 10 in 100 people)
(fewer than 1 in 100 people)
(fewer than 1 in 1000 people at high doses)
Stomach pain and cramps
Thrush (candida infection)
Severe allergic reaction
Infection with other bacteria (Clostridium difficile-associated disease)
Ear problems (dizziness, hearing loss, ringing in the ears [tinnitus])
Liver problems (cholestatic hepatitis)
Inflamed pancreas (pancreatitis)
Slowed heart rate
Note: this is not a complete list of all the possible side effects of azithromycin.

Antibiotics and allergic reactions

Some people experience an allergic reaction to azithromycin or other antibiotics. This is due to an over-reaction of their immune system to the antibiotic.

Symptoms of an allergic reaction can include:

  • hives (large, red raised areas on the skin)
  • swollen lips, tongue or mouth
  • fever (a temperature of 38.5°C or higher)
  • breathing problems
  • fainting.

Seek medical advice if you experience any of these symptoms while you are taking an antibiotic.

It is not known why this happens to some people and not others, but it may mean that you will have to avoid taking the antibiotic in the future. There are other types of antibiotics which don’t cause this reaction that will be suitable for you.

Read more about the common side effects of antibiotics.

Skin sensitivity with azithromycin

Azithromycin and related antibiotics (macrolide antibiotics) can cause your skin to be more sensitive to sunlight than usual. If your skin is exposed to sunlight, you may develop a rash, itching and redness.

If you will be spending time outside, particularly between 10am and 3pm, make sure you protect your skin by wearing sunscreen (factor 30 or higher), and wear a hat and protective clothing.

Who can I ask about side effects?

If you’re concerned that you or someone in your care may have had side effects related to a medicine, seek medical advice. People with questions about their medicines or seeking general information about side effects can also call the NPS Medicines Line on 1300 633 424 (Monday-Friday, 9am-5pm AEST). To report possible side effects call the Adverse Medicine Events (AME) line on 1300 134 237 from anywhere in Australia (Monday–Friday, 9am–5pm AEST).

  • Rossi S, ed. Australian Medicines Handbook [online]. Adelaide: AMH, July 2012.
  • Sweetman S, ed. Martindale: The complete drug reference [online]. London: Pharmaceutical Press (accessed 18 October 2011).
  • Antibiotic Expert Group. Therapeutic Guidelines: Azithromycin. Melbourne: Therapeutic Guidelines Limited, 2012 (accessed 27 March 2012).