Why is this medication prescribed?
Azithromycin is used to treat certain bacterial infections, such as bronchitis; pneumonia; sexually transmitted diseases (STD); and infections of the ears, lungs, sinuses, skin, throat, and reproductive organs. Azithromycin also is used to treat or prevent disseminated Mycobacterium avium complex (MAC) infection [a type of lung infection that often affects people with human immunodeficiency virus (HIV)]. Azithromycin is in a class of medications called macrolide antibiotics. It works by stopping the growth of bacteria. Antibiotics will not kill viruses that can cause colds, flu, or other infections.
How should this medicine be used?
Azithromycin comes as a tablet, an extended-release (long-acting) suspension (liquid) and a suspension (liquid) to take by mouth. The tablets and suspension (Zithromax) are usually taken with or without food once a day for 1 to 5 days. When used for the prevention of disseminated MAC infection, azithromycin tablets are usually taken with or without food once weekly. The extended-release suspension (Zmax) is usually taken on an empty stomach (at least 1 hour before or 2 hours after a meal) as a one-time dose. To help you remember to take azithromycin, take it around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take azithromycin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Shake the liquid well before each use to mix the medication evenly. Use a dosing spoon, oral syringe, or measuring cup to measure the correct amount of medication. Rinse the measuring device with water after taking the full dose of medication.
If you receive azithromycin powder for suspension in the single-dose, 1-gram packet, you must first mix it with water before you take the medication. Mix the contents of the 1-gram packet with 1/4 cup (60 mL) of water in a glass and consume the entire contents immediately. Add an additional 1/4 cup (60 mL) of water to the same glass, mix, and consume the entire contents to ensure that you receive the entire dose.
If you receive azithromycin extended-release suspension as a dry powder you must first add water to the bottle before you take the medication. Open the bottle by pressing down on the cap and twisting. Measure 1/4 cup (60 mL) of water and add to the bottle. Close the bottle tightly and shake well to mix.
Use the extended-release liquid within 12 hours of receiving it from the pharmacy or adding water to the powder.
If you vomit within an hour after taking azithromycin, call your doctor right away. Your doctor will tell you if you need to take another dose. Do not take another dose unless your doctor tells you to do so.
You should begin to feel better during the first few days of treatment with azithromycin. If your symptoms do not improve, or get worse, call your doctor.
Take azithromycin until you finish the prescription, even if you feel better. Do not stop taking azithromycin unless you experience the severe side effects described in the SIDE EFFECTS section. If you stop taking azithromycin too soon or skip doses, your infection may not be completely treated and the bacteria may become resistant to antibiotics.
Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.
Other uses for this medicine
Azithromycin is also used sometimes to treat H. pylori infection, travelers' diarrhea, and other gastrointestinal infections; Legionnaires' disease (a type of lung infection); pertussis (whooping cough; a serious infection that can cause severe coughing); and babesiosis (an infectious disease carried by ticks). It is also used to prevent heart infection in people having dental or other procedures, and to prevent STD in victims of sexual assault. Talk to your doctor about the possible risks of using this medication for your condition.
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
What special precautions should I follow?
Before taking azithromycin,
- tell your doctor and pharmacist if you are allergic to azithromycin, clarithromycin (Biaxin, in Prevpac), dirithromycin (not available in the U.S.), erythromycin (E.E.S., E-Mycin, Erythrocin), telithromycin (Ketek), any other medications, or any of the ingredients in azithromycin tablets or suspension (liquid). Ask your pharmacist for a list of the ingredients.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: anticoagulants ('blood thinners') such as warfarin (Coumadin, Jantoven); cyclosporine (Neoral, Sandimmune); digoxin (Lanoxin); dihydroergotamine (D.H.E. 45, Migranal); ergotamine (Ergomar); medications for irregular heartbeat such as amiodarone (Cordarone, Pacerone), dofetilide (Tikosyn), procainamide (Procanbid), quinidine, and sotalol (Betapace, Sorine); nelfinavir (Viracept); phenytoin (Dilantin); and terfenadine (not available in the U.S.). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- if you are taking antacids containing aluminum hydroxide or magnesium hydroxide (Maalox, Mylanta, Tums, others), you will need to allow some time to pass between when you take a dose of these antacids and when you take a dose of azithromycin tablets or liquid. Ask your doctor or pharmacist how many hours before or after you take azithromycin you may take these medications. The extended-release suspension may be taken at any time with antacids.
- tell your doctor if you have ever had jaundice (yellowing of the skin or eyes) or other liver problems while taking azithromycin. Your doctor will probably tell you not to take azithromycin.
- tell your doctor if you or anyone in your family has or has ever had a prolonged QT interval (a rare heart problem that may cause irregular heartbeat, fainting, or sudden death) or a fast, slow, or irregular heartbeat, and if you have low levels of magnesium or potassium in your blood; if you have a blood infection; heart failure; cystic fibrosis; AIDS or human immunodeficiency virus (HIV) infection; myasthenia gravis (a condition of muscles and the nerves that control them); or if you have kidney or liver disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking azithromycin, call your doctor.
What special dietary instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What should I do if I forget a dose?
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What side effects can this medication cause?
Azithromycin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- stomach pain
Some side effects can be serious. If you experience any of these symptoms, stop taking azithromycin and call your doctor immediately or get emergency medical treatment:
- fast, pounding, or irregular heart beat
- wheezing or difficulty breathing or swallowing
- swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
- mouth sores
- severe diarrhea (watery or bloody stools) that may occur with or without fever and stomach cramps (may occur up to 2 months or more after your treatment)
- yellowing of the skin or eyes
- extreme tiredness
- unusual bleeding or bruising
- lack of energy
- loss of appetite
- pain in the upper right part of the stomach
- flu-like symptoms
- dark-colored urine
- blisters or peeling of the skin
- unusual muscle weakness or difficulty with muscle control
Azithromycin may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at http://www.fda.gov/Safety/MedWatch] or by phone [1-800-332-1088].
What should I know about storage and disposal of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store azithromycin tablets and suspension at room temperature and away from excess heat and moisture (not in the bathroom). Do not refrigerate or freeze the suspension. Throw away any azithromycin suspension that is left over after 10 days and any medication that is outdated or no longer needed. Throw away any unused extended-release azithromycin suspension after dosing is complete. Talk to your pharmacist about the proper disposal of your medication.
In case of emergency/overdose
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
What other information should I know?
Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to azithromycin.
Do not let anyone else take your medication. Your prescription is probably not refillable. If you still have symptoms of infection after you finish the azithromycin, call your doctor.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
- Zithromax® Single Dose Packets
- Zithromax® Tri-Paks®
- Zithromax® Z-Paks®