Zmax (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. Zmax belongs to a group of drugs called macrolide antibiotics. It works by preventing the growth of bacteria.
This medication comes in an extended-release liquid form, and in single-dose packets to be mixed with water. Zmax is taken as one dose, on an empty stomach.
Common side effects of Zmax include diarrhea, nausea, stomach pain, and headache.
Zmax is a prescription medicine used in adults and in children over the age of 6 months to treat certain kinds of pneumonia (lung infections), sinus infections, and other infections caused by bacteria.
This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.
Zmax 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 Zmax.
The most common side effects in adults are:
- Diarrhea/loose stools
- Stomach pain
The most common side effects in children are:
- Diarrhea/loose stools
- Stomach pain
This is not a complete list of Zmax 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)
- 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 Zmax drug interactions. Ask your doctor for more information.
Heart rhythm changes. Zmax 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 Zmax.
Zmax can cause serious allergic reaction. You should not take Zmax 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 Zmax there are no specific foods that you must exclude from your diet when receiving Zmax.
Before you start Zmax tell your doctor about all your medical problems including if you:
- have heart rhythm problems (QT prolongation, Torsades de Pointes)
- have liver problems
- have kidney problems
- have myasthenia gravis
- are pregnant or breastfeeding
Tell your doctor about all the medicines you take, including prescription and nonprescription medicines, vitamins and herbal supplements.
Tell your doctor if you are pregnant or plan to become pregnant. It is not known if Zmax will harm your unborn baby.
Tell your doctor if you are breastfeeding or plan to breastfeed. It is not known if Zmax is excreted in human breast milk or if it will harm your nursing baby.
If you get Zmax in liquid form, it is ready to take.
If you get Zmax as dry powder, you must add water to the bottle before you take it. To prepare Zmax:
- Open the bottle: To open the bottle, press down on the cap and twist.
- Use a measuring cup to add 60 mL (1/4 cup) water to the Zmax bottle.
- Tightly close the bottle and shake to mix it.
- Keep Zmax at room temperature between 59ºF to 86ºF (15 to 30ºC).
- Shake the bottle well before using.
- Take Zmax within 12 hours after it has been prepared by the pharmacy or you add water to the powder.
- Take Zmax exactly how your doctor prescribes it. This will help to treat your infection and decrease the chance that Zmax or other antibiotics will not work to treat infections in the future.
- Adults: take all the medicine in the bottle.
- Children: give your child the amount of Zmax prescribed by your doctor and throw away the rest of the medicine.
- To be sure that you give your child the right dose of Zmax, use a dosing spoon, medicine syringe, or cup.
- Take Zmax on an empty stomach (at least 1 hour before eating or 2 hours after eating).
- You can take antacids with Zmax.
- If you throw up (vomit) within one hour of taking Zmax, call your doctor right away to see if more medicine is needed.
Zmax needs time to work, so you or your child may not feel better right away. If you or your child’s symptoms do not get better in a few days, call your doctor.
Take Zmax exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.
Zmax should be taken as a single 2 g dose. Zmax provides a full course of antibacterial therapy in a single oral dose. It is recommended that Zmax be taken on an empty stomach (at least 1 hour before or 2 hours following a meal).
For children 6 months and older, Zmax should be taken as a single dose of 60 mg/kg (equivalent to 27 mg/lb) body weight. The Zmax dose in mL is equivalent to the child's weight in lb (1 mL/lb dose), for a body weight of less than 75 lb (34 kg). It is recommended that Zmax be taken on an empty stomach (at least 1 hour before or 2 hours following a meal).
Children weighing 75 lb (34 kg) or more should receive the adult dose (2 g).
If you take too much Zmax, call your local Poison Control Center or seek emergency medical attention right away.
Active ingredient: azithromycin dihydrate
Inactive ingredients: glyceryl behenate, poloxamer 407, sucrose, sodium phosphate tribasic anhydrous, magnesium hydroxide, hydroxypropyl cellulose, xanthan gum, colloidal silicon dioxide, titanium dioxide, artificial cherry flavor, and artificial banana flavor
Before constitution, store dry powder at or below 30°C (86°F).
After constitution, store suspension at 25°C (77°F); excursions permitted to 15–30°C (59–86°F) [see USP Controlled Room Temperature]. Do not refrigerate or freeze.
Constituted suspension should be consumed within 12 hours. For adult patients, the entire bottle should be consumed. For pediatric patients, any suspension remaining after dosing MUST be discarded.
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