Zithromax (generic: azithromycin) is a prescription medication used to treat many bacterial infections such as bronchitis, pneumonia, sexually transmitted diseases, and infections of the ear, sinuses, skin, and throat. Zithromax belongs to a group of drugs called macrolide antibiotics. It works by preventing the growth of bacteria.
This medication comes in tablet and liquid forms. An extended-release liquid form (Zmax) is also available. Zithromax is usually taken once daily, with or without food.
Common side effects of Zithromax include diarrhea, stomach pain, and nausea.
Zithromax is a prescription medication used to treat bacterial infections of the ear, lung, skin and throat.
This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.
Like all medicines, Zithromax may cause side effects. The most common side effects are:
- abdominal (stomach area) pain
Zithromax may cause serious side effects. Call your doctor right away or get emergency treatment if you have any of the following:
Abnormal heart rhythm. Tell your doctor right away if you feel your heart beating in your chest or an abnormal heart beat, get dizzy, or faint. See "Drug Precautions" section.
Serious allergic reaction or serious skin reaction: Get emergency help right away if you have:
- Hives, skin rash, sores in your mouth, or your skin blisters and peels
- Trouble swallowing
- Swelling of your face, eyes, lips, tongue or throat
- Wheezing or trouble breathing
Diarrhea: Call your doctor right away if you have diarrhea that does not go away, is severe, watery, or has blood in it. Diarrhea can occur as late as two or months after you take an antibiotic such as
This is not a complete list of Zithromax side effects. Ask your doctor or pharmacist for more information.
Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:
- medications that cause QT prolongation (changes in heart rhythm)
- antacids containing aluminum or magnesium (Maalox, Mylanta, Rolaids, others)
- anticoagulants ('blood thinners') such as warfarin (Coumadin, Jantoven)
- carbamazepine (Carbatrol, Epitol, Equetro, Tegretol, Tegretol XR)
- cyclosporine (Gengraf, Neoral, Sandimmune)
- digoxin (Lanoxin)
- dihydroergotamine (D.H.E. 45, Migranal)
- ergotamine (Ergomar)
- medications that suppress the immune system
- nelfinavir (Viracept)
- phenytoin (Dilantin)
- tacrolimus (Prograf, Protopic)
- terfenadine (Seldane)
- theophylline (Theo-24, Uniphyl, TheoCap, Theochron)
- triazolam (Halcion)
This is not a complete list of Zithromax drug interactions. Ask your doctor or pharmacist for more information.
Heart rhythm changes. Zithromax can cause abnormal changes in the electrical activity of the heart that may lead to a potentially life-threatening irregular heart rhythm. Patients are at a higher risk for developing this condition if they have the following risk factors:
- existing heart rhythm problems called QT prolongation
- low blood levels of potassium or magnesium
- slower than normal heart rate
- use of drugs for the treatment of abnormal heart rhythms or arrhythmias
If you have any of the above conditions, talk to your doctor before taking Zithromax.
Zithromax can cause serious allergic reaction. Do not take Zithromax if you are allergic to this or similar antibiotics (clarithromycin, dirithromycin, erythromycin) without discussing with your doctor.
Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of Zithromax there are no specific foods that you must exclude from your diet when receiving Zithromax.
Before you start Zithromax, be sure to tell the doctor if you have any medical conditions including if you:
- have irregular heartbeat (see "Drug Precautions")
- have ever had any liver or kidney problems
- have cystic fibrosis
- have human immunodeficiency virus (HIV)
- are allergic to any medicines
- are allergic to certain antibiotics such as erythromycin
- are allergic to azithromycin or any of the ingredients of Zithromax
Tell your doctor if you are pregnant or breastfeeding.
Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.
Tell your doctor if you are pregnant or plan to become pregnant. It is not known if Zithromax will harm your unborn baby.
Tell your doctor if you are breastfeeding or plan to breastfeed. It is not known if Zithromax is excreted in human breast milk or if it will harm your nursing baby.
Zithromax comes in tablet and liquid forms. It is usually taken once daily, for 1 to 5 days.
- Take Zithromax at the same time each day.
- Take each dose with a full glass of water.
- Zithromax can be taken with or without food. Try taking Zithromax with food if you have an upset stomach.
- Finish the prescription, even if you begin to feel better, unless your doctor tells you to stop.
Take Zithromax exactly as prescribed by your doctor. Follow the directions on your prescription label carefully. Your doctor will determine the best dose for you or your child based on the type of infection and the patient's age.
The recommended Zithromax dosage for most infections is 250 mg or 500 mg once daily. Zithromax is usually taken for 3 to 5 days, or longer for more serious infections. For some infections a single 1 or 2 g dose is prescribed.
The recommended Zithromax dose in children is based on weight and ranges from 5 mg to 20 mg per kilogram of body weight per day. Zithromax is usually taken for 3 to 5 days.
If you take too much Zithromax, call your local Poison Control Center or seek emergency medical attention right away.
Zithromax tablets are available in 250 mg and 500 mg strengths.
Zithromax for oral suspension is available in 100 mg/5 mL or 200 mg/5 mL bottles containing: 300 mg, 600 mg, 900 mg, and 1200 mg Azithromycin.
- Active Ingredient: azithromycin
- Inactive Ingredients (tablets): anhydrous dibasic calcium phosphate, croscarmellose sodium, magnesium stearate, sodium lauryl sulfate, hypromelloses, lactose, titanium dioxide, triacetin, D&C Red. no. 30, and aluminum oxide.
- Inactive Ingredients (suspension): sucrose, tribasic anhdrous sodium phosphate, hydroxypropyl cellulose, xanthan gum, FD&C Red no. 40, Cherry, Vanilla, Banana flavor.
Keep Zithromax and all medications out of the reach of children.
- Zithromax can be stored at room temperature.
- You do not have to keep oral suspension in the refrigerator.
- Throw away any medicine that is left over after treatment.
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