What Is Clarithromycin?

Clarithromycin is an antibiotic prescribed to treat bacterial infections. It belongs to the class of antibiotics called macrolides.

Clarithromycin is available as a tablet, extended-release tablet, and liquid suspension. The brand name of clarithromycin is Biaxin. 

Clarithromycin is considered a broad-spectrum antibiotic, meaning it is effective against a wider range of bacterial infections. It has been shown to have activity against Gram-positive and Gram-negative bacteria, some anaerobes, and atypical pathogens. 

How Does Clarithromycin Work?

One way that clarithromycin works is by binding to a bacteria’s ribosome and preventing it from creating the proteins needed by the bacteria to live. 

The ribosome is a tiny structure inside the bacteria’s cell that builds proteins. When clarithromycin binds to the ribosome, the ribosome produces incomplete proteins that the bacteria cannot use, preventing them from growing and reproducing. The bacteria eventually die, and then the immune system can clear the infection. 

Depending on the type of bacteria causing the infection and the drug concentration prescribed, clarithromycin might follow the above steps and inhibit its growth, or it may directly kill the bacteria. 

What Is Clarithromycin Used For?

Clarithromycin is used to treat bacterial infections such as:

• skin infections (e.g., cellulitis)
• chest infections (e.g., pneumonia, bronchitis)
• ear infections

This list is not complete and clarithromycin may be used to treat other infections.

Clarithromycin may also be prescribed alongside other medications (e.g., rifampin, ethambutol, lansoprazole, amoxicillin, bismuth, omeprazole) to treat stomach ulcers resulting from Helicobacter pylori (H. pylori). 

Side Effects of Clarithromycin

Common side effects of clarithromycin may consist of:

• diarrhea
• stomach pain
• nausea
• vomiting
• unusual or unpleasant taste in the mouth
• headache

These side effects are generally mild and do not last long. 

Some more serious side effects of clarithromycin include:

• fluttering in your chest
• fast or pounding heartbeat
• sudden dizziness
• shortness of breath
• severe stomach pain
• watery or bloody diarrhea
• spinning sensation
• confusion
• kidney problems (swelling of the feet or ankles, little or no urination, feeling tired)
• liver problems (upper stomach pain, loss of appetite, dark urine, tiredness, clay-colored stools, yellowing of the skin or eyes)

If you experience any of these symptoms, contact a doctor immediately. 

Some people may be allergic to clarithromycin. These allergic reactions may present with symptoms such as difficulty breathing, hives, and facial or throat swelling. Clarithromycin may also cause a severe skin reaction with a sore throat, skin pain, purple or red skin rash, blistering and peeling skin, or burning in the eyes. If you experience an allergic or severe skin reaction from clarithromycin, seek emergency medical help. 

How to Take Clarithromycin?

Clarithromycin should be taken exactly as a doctor prescribes, including the dosage amount and timing. Do not take more clarithromycin than prescribed or for longer than recommended. Furthermore, only take clarithromycin to treat the condition it is prescribed for. 

Taking clarithromycin for its entire prescription length is crucial, even if your symptoms get better. It’s common for symptoms to improve before the infection is completely cleared, and discontinuing your medication early increases the risk of the infection remaining. 

Clarithromycin tablets and liquid suspensions can be taken with or without food. If you notice that taking clarithromycin upsets your stomach, taking it with food may help ease this symptom.  However, those taking the extended-release tablets should take them with food, and it is important to swallow the tablets whole––do not chew, crush, or break them. 

Sometimes, clarithromycin is prescribed alongside other drugs, so it is important to follow the instructions for each drug to ensure you are receiving the most from your treatment. 

If you miss a dose of clarithromycin, take it as soon as you remember. However, skip the missed dose if it is almost time for your next dose. Do not take extra medicine to make up for the missed dose.