Key takeaways:
Biaxin (clarithromycin) is a macrolide antibiotic that treats certain bacterial infections. It’s generally well-tolerated, and side effects typically resolve after your treatment course is finished.
Common Biaxin side effects include nausea, diarrhea, and taste changes. Stomach pain and heartburn are also possible.
Rare but serious Biaxin side effects include severe diarrhea, an irregular heart rate, and liver problems. Allergic reactions are also possible. Seek medical care for any side effects that seem severe or life-threatening.
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Biaxin (clarithromycin) is an antibiotic that helps treat different bacterial infections, such as pneumonia or sinus infections. Like all medications, Biaxin can cause side effects. Most are mild, such as stomach upset or changes in taste, but some can be more serious. Knowing what to watch for can help you stay safe during treatment.
Biaxin side effects at a glance
Below is a list of common and rare Biaxin side effects that can occur during treatment. Keep in mind that this isn’t a complete list. Discuss any concerns about side effects that occur while taking Biaxin with your prescriber, even if they aren’t listed below.
Common Biaxin side effects include:
Stomach pain
Diarrhea
Nausea and vomiting
Altered sense of taste
Heartburn
Gas
Headache
Vaginal yeast infection
Rare but serious Biaxin side effects include:
Irregular heartbeat
Liver problems
Clostridioides difficile diarrhea (C. diff colitis)
Drug-resistant bacteria
Dizziness
Low blood cell counts
Although not a side effect, Biaxin may also cause an allergic reaction for some people. Stop taking Biaxin and seek medical care if you develop a rash or have swelling of your face, mouth, or throat after taking it.
Let’s take a closer look at five Biaxin side effects and what to do if they occur.
1. Stomach issues
Stomach issues are the most common Biaxin side effect. These include stomach pain, nausea and vomiting, and heartburn.
Taking Biaxin with food may help reduce stomach-related side effects. It also comes in an extended-release version (Biaxin XL) that may be easier on your stomach.
If you vomit after taking Biaxin, reach out to your prescriber for guidance. They can let you know if you need to repeat your dose. In most cases, stomach issues will go away once your course of Biaxin treatment is complete. But if they’re severe, let your prescriber know. A different antibiotic may be a better fit for you.
2. Diarrhea
Diarrhea is another possible Biaxin side effect. As with stomach issues, it will usually resolve once your course of Biaxin is finished.
Drink plenty of fluids if you have diarrhea to prevent dehydration. Avoiding fried, spicy, or processed foods can also help. But if your diarrhea is severe or bothersome, talk to your prescriber to see if an over-the-counter diarrhea medication is a safe option for you.
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In rare cases, Biaxin can cause a severe form of diarrhea known as C. diff colitis. This happens when Biaxin kills off healthy bacteria in your gut, allowing C. diff to overgrow. Symptoms of this include severe, watery diarrhea; stomach cramps; and fever. Seek emergency care if these symptoms appear while you’re taking Biaxin or in the weeks after.
3. Taste changes
Biaxin may cause taste changes, such as a metallic taste in your mouth. The oral liquid form of the medication is also known to have a very unpleasant taste that can linger in the mouth. This can create a challenge when getting young children to take it.
Taste changes should resolve once you finish taking Biaxin. In the meantime, try sugar-free mints or gum to help. And remember to stay hydrated, as dry mouth can make taste changes worse.
If your child is taking the oral liquid, ask the pharmacist about flavoring options to help with the taste. You can also try having your child eat an ice pop or other cold foods to help numb the taste buds before taking the medication.
4. Irregular heart rate
Biaxin and other macrolide antibiotics can raise the risk of an irregular heart rate, known as QT prolongation. If this happens, you may feel lightheaded or dizzy, or notice your heart beating differently than usual.
The risk of QT prolongation is higher if you’re age 65 or older, take other medications with this side effect, or have an existing arrhythmia (irregular heart rate). Let your prescriber know if any of these apply to you before taking Biaxin. A different antibiotic may be a better fit for you.
5. Liver problems
In rare cases, Biaxin may cause liver problems. It may cause an increase in your liver enzyme levels. But this typically doesn’t cause symptoms and goes away on its own once treatment is finished.
More serious liver problems are also possible.They typically appear within 1 to 3 weeks after starting Biaxin, but they can also appear after treatment is finished. Symptoms can include yellowing of the eyes and skin (jaundice), stomach pain, and dark-colored urine. Seek medical care if these symptoms appear during or after taking Biaxin.
The bottom line
Biaxin (clarithromycin) is an antibiotic that helps treat different bacterial infections. Most Biaxin side effects, such as stomach problems or taste changes, are mild and go away after treatment ends. But it’s important to watch for serious symptoms, such as a fast or uneven heartbeat, yellowing skin, or severe diarrhea. These could be signs of more serious Biaxin side effects that require medical attention. Always talk to your prescriber or pharmacist if you have questions or concerns about Biaxin side effects.
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References
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LiverTox: Clinical and Research Information on Drug-Induced Liver Injury. (2017). Clarithromycin. National Institute of Diabetes and Digestive and Kidney Diseases.
Patel, P. H., et al. (2023). Macrolides. StatPearls.
Surawicz, C. M., et al. (2021). C. difficile infection (CDI) overview.
