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Generic Name: azithromycin (a ZITH roe MYE sin)
Brand Names: Zithromax, Zmax

What is azithromycin?

Zithromax (azithromycin) is an antibiotic that fights bacteria.

Zithromax is used to treat many different types of infections caused by bacteria, such as respiratory infections, skin infections, ear infections, and sexually transmitted diseases.

Zithromax may also be used for purposes not listed in this medication guide.

Important information

You should not use Zithromax if you have ever had jaundice or liver problems caused by taking azithromycin.

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Before taking this medicine

You should not use Zithromax if you are allergic to azithromycin, or if:

  • you have ever had jaundice or liver problems caused by taking Zithromax; or

  • you are allergic to similar drugs such as clarithromycin, erythromycin, or telithromycin.

To make sure Zithromax is safe for you, tell your doctor if you have:

  • liver disease;

  • kidney disease;

  • myasthenia gravis;

  • a heart rhythm disorder; or

  • a history of Long QT syndrome.

Zithromax is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether azithromycin passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Do not give Zithromax to a child younger than 6 months old.

How should I take Zithromax?

Take Zithromax exactly as prescribed by your doctor. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended. The dose and length of treatment with azithromycin may not be the same for every type of infection.

Zithromax can be taken with or without food.

Shake the oral suspension (liquid) well just before you measure a dose. Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

Use this medicine for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Skipping doses may also increase your risk of further infection that is resistant to antibiotics. Zithromax will not treat a viral infection such as the flu or a common cold.

Store at room temperature away from moisture and heat. Throw away any unused liquid medicine after 10 days.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Zithromax?

Do not take antacids that contain aluminum or magnesium within 2 hours before or after you take Zithromax. This includes Acid Gone, Aldroxicon, Alternagel, Di-Gel, Gaviscon, Gelusil, Genaton, Maalox, Maldroxal, Milk of Magnesia, Mintox, Mylagen, Mylanta, Pepcid Complete, Rolaids, Rulox, and others. These antacids can make Zithromax less effective when taken at the same time.

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, stop taking Zithromax and call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.

Avoid exposure to sunlight or tanning beds. Zithromax can make you sunburn more easily. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

Zithromax side effects

Get emergency medical help if you have signs of an allergic reaction to Zithromax: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • severe stomach pain, diarrhea that is watery or bloody;

  • headache with chest pain and severe dizziness, fainting, fast or pounding heartbeats;

  • liver problems - nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);

  • severe skin reaction - fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Older adults may be more likely to have side effects on heart rhythm, including a life-threatening fast heart rate.

Common Zithromax side effects may include:

  • diarrhea;

  • nausea, vomiting, stomach pain; or

  • headache.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Zithromax?

Tell your doctor about all your current medicines and any you start or stop using, especially:

  • nelfinavir; or

  • a blood thinner - warfarin, Coumadin, Jantoven.

This list is not complete. Other drugs may interact with azithromycin, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your pharmacist can provide more information about Zithromax.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Zithromax only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date, and complete, but no guarantee is made to that effect. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2015 Cerner Multum, Inc. Version: 17.03. Revision Date: 2015-08-31, 12:53:35 PM.