Z-Pak Dosage Guide: Common Zithromax Dosing - GoodRx (2024)

There’s a good chance you’ve been prescribed, or at least heard of, a Z-Pak. It contains a “sheet” or blister card of six tablets of azithromycin (Zithromax), a macrolide antibiotic that prevents the growth of certain bacteria. This medication has been around for decades and is generally well tolerated.

Pre-packaged into a ready-to-use dose pack, Z-Paks can treat a variety of mild to moderate bacterial infections, such strep throat, pneumonia, and ear infections. And because azithromycin’s dosing is the same for many people, the Z-Pak allows for a convenient way to prescribe, fill, and take the medication.

This prescription-only product contains the exact number of tablets at the necessary dosage to treat a variety of infections. But a few things can still affect your Z-Pak dosage, such as your age and other medications you take.

What’s the typical Z-Pak dosage for adults?

A Z-Pak contains six 250 mg azithromycin tablets. These tablets are taken for 5 days in a row. On the first day of treatment, you’ll likely take two tablets (500 mg total) by mouth. On days 2 through 5, you’ll drop down to one tablet per day.

This is different from the Tri-Pak, which contains three 500 mg tablets of azithromycin. One tablet is taken daily for 3 days. Azithromycin is also available as tablets in prescription bottles (similar to other prescription tablets without the dose pack) as well as an oral suspension. Your healthcare provider will decide which azithromycin formulation is best to treat your infection.

Just like with any other antibiotic, it’s important to take azithromycin exactly as prescribed. Even though you may begin to feel better after a couple days, it’s important to take all of the tablets in the package. There’s a chance your infection could return if you don’t complete the full treatment. What’s more, antibiotic resistance — when an antibiotic doesn’t work against a certain bacteria anymore — could develop, making it harder to treat a future infection.

Taking your medication at the same time every day is a helpful way to remember to take it consistently. You also can take azithromycin with or without food. However, if you experience diarrhea or an upset stomach after taking it, try taking your next dose with food to help minimize these side effects.

What’s the typical Z-Pak dosage for children?

Azithromycin can treat bacterial infections in children. It can be prescribed to children as young as 6 months old when treating ear infections and pneumonia. This age requirement is slightly higher for tonsil infections and strep throat — it can be given to children ages 2 years and older.

Azithromycin dosing for children is based on the child’s body weight. For example, a typical dose of azithromycin for the treatment of strep throat is 12 mg per kg of body weight by mouth once daily for 5 days. For a child weighing 20 kg (44 lbs), this would translate to a 240 mg daily dose. This may be rounded up to 250 mg for simplicity’s sake. Your child’s healthcare provider will calculate the correct dose for your child.

Are there any Z-Pak dosage adjustments for medical conditions?

There aren’t any medical conditions that require Z-Pak dose adjustments. However, caution is needed when azithromycin is prescribed to people with certain medical conditions. Liver and heart problems are top of mind.

Before taking azithromycin, notify your provider if you have a history of liver problems. Z-Paks should be avoided altogether if you have a history of severe liver dysfunction or jaundice (yellowing of the skin or eyes).

Z-Paks can also affect your heart rhythm. It has the ability to cause QT prolongation, a condition that can happen when your heart takes more time to reset during beats. This can be life-threatening. The risk of QT prolongation is higher when azithromycin is combined with certain health conditions, such as heart rhythm problems, or medications like amiodarone (Pacerone).

These interactions can be prevented by telling your healthcare provider about your health history as well as all medications you’re currently taking. But if you experience a fast or irregular heartbeat, chest pain, or dizziness while taking your Z-Pak, make sure to talk to your provider right away.

What happens if you miss a dose of azithromycin?

Taking your antibiotic consistently helps maximize its effectiveness. So if you miss a dose of your Z-Pak prescription, take it as soon as you remember. But skip the dose altogether if it’s close to the time of your next scheduled dose. At that point, just take your next dose as planned.

Don’t double up on doses either. This can increase the risk of experiencing azithromycin side effects. If you miss a dose, you can still complete the entire treatment course by taking all of the tablets in the Z-Pak. You may just need to add an extra day or two onto your original schedule.

Still, it’s natural to forget to take a medication dose from time to time. Thankfully, there are tools that can help you remember to take it on time and as planned. For example, setting an alarm for a certain time of day (like after a meal) can be helpful. Medication reminder apps are also useful ways to alert you when a medication should be taken. There are several apps that you can easily download onto your smartphone.

What should you do if you take too much azithromycin?

If you accidentally take one or two extra azithromycin doses, don’t panic. Tablet dosages found in a Z-Pak are relatively small. In fact, higher doses (up to 1 to 2 grams) of azithromycin are actually prescribed for certain conditions, such as urethra and cervix infections.

However, you may experience a few additional side effects after taking extra doses. Common side effects you may experience include diarrhea, nausea, and abdominal pain. Implementing changes in your diet, such as eating bland and starchy foods, can be helpful in managing these symptoms if you experience them. The risk of these side effects goes up as larger amounts of azithromycin are taken.

More serious side effects are also possible when taking azithromycin — especially at very high doses. Although rare, liver damage can occur and can be life-threatening in some people. Contact your healthcare provider right away if you notice yellowing of your skin, have dark-colored urine, or experience intense stomach pain.

If you believe you or your child has taken too much azithromycin, it’s best to contact your healthcare provider as a precaution. They can determine next steps and guide you appropriately depending on the situation. Contacting Poison Control at 1-800-222-1222 is another option. But if you’re experiencing severe symptoms, it’s better to seek emergency care right away instead.

How to save on your Z-Pak

The “Z-Pak” is a nickname for the prepackaged form of azithromycin, and it’s available both as a brand-name and generic medication. GoodRx can help you save over 80% off the average retail price of the generic version. Generic azithromycin’s price at certain pharmacies is as low as $8.96 with a free GoodRx discount.