Clarithromycin (Biaxin®)

About This Drug

Clarithromycin is an antibiotic and is often used to treat bacterial infections. It is sometimes used in combination to treat helicobacter pylori and can be used in combination with other drugs to treat cancer. It is given orally (by mouth).

Possible Side Effects

  • Nausea and vomiting (throwing up)
  • Diarrhea (loose bowel movements)
  • Indigestion
  • Pain in your abdomen
  • Changes in the way food and drinks taste

Note: Not all possible side effects are included above

Warnings and Precautions 

  • Changes in your liver function.
  • Abnormal heart beat and/or abnormal EKG.
  • Severe diarrhea, that can be caused by an infection called clostridium difficile.
  • Risk of developing myasthenia gravis, which is an autoimmune disorder that cause rapid weakness of several types of muscles in your body, which can be serious. If you already have myasthenia gravis, clarithromycin may make it worse.
  • Increased risk of life-threatening side effects in patients with existing heart disease.
  • Allergic reactions, including anaphylaxis are rare but may happen in some patients, and may be life-threatening. Signs of allergic reaction to this drug may be swelling of the face, feeling like your tongue or throat are swelling, trouble breathing, rash, itching, fever, chills, feeling dizzy, and/or feeling that your heart is beating in a fast or not normal way. If this happens, do not take another dose of this drug. You should get urgent medical treatment.

Note: Some of the side effects above are very rare. If you have concerns and/or questions, please discuss them with your medical team.

How to Take Your Medication 

  • Swallow the medicine with or without food. Can be taken with milk.
  • Missed dose: If you vomit or miss a dose, take your next dose at the regular time. Do not take 2 doses at the same time, instead, continue with your regular dosing schedule and contact your physician.
  • Storage: Store this medicine in the original container, with lid tightly closed, at room temperature. Protect from light.

Treating Side Effects 

  • Drink plenty of fluids (a minimum of eight glasses per day is recommended).
  • If you throw up or have loose bowel movements, you should drink more fluids so that you do not become dehydrated (lack of water in the body from losing too much fluid).
  • If you have diarrhea, eat low-fiber foods that are high in protein and calories and avoid foods that can irritate your digestive tracts or lead to cramping.
  • Ask your nurse or doctor about medicine that can lessen or stop your diarrhea.
  • To help with nausea and vomiting, eat small, frequent meals instead of three large meals a day. Choose foods and drinks that are at room temperature. Ask your nurse or doctor about other helpful tips and medicine that is available to help stop or lessen these symptoms.
  • Keeping your pain under control is important to your well-being. Please tell your doctor or nurse if you are experiencing pain.
  • Taking good care of your mouth may help food taste better and improve your appetite

Food and Drug Interactions 

  • There are no known interactions of clarithromycin with food.
  • Check with your doctor or pharmacist about all other prescription medicines and over-the-counter medicines and dietary supplements (vitamins, minerals, herbs and others) you are taking before starting this medicine as there are known drug interactions with clarithromycin. Also, check with your doctor or pharmacist before starting any new prescription or over-the-counter medicines, or dietary supplements to make sure that there are no interactions.
  • Avoid the use of St. John’s Wort while taking clarithromycin as this may lower the levels of the drug in your body, which can make it less effective.

When to Call the Doctor

Call your doctor or nurse if you have any of these symptoms and/or any new or unusual symptoms:

  • Headache that does not go away
  • Droopy eyelid and mouth
  • Blurred vision or other changes in eyesight
  • Severe muscle weakness in your arms and/or legs
  • Trouble speaking
  • Feeling that your heart is beating in a fast or not normal way (palpitations)
  • Nausea that stops you from eating or drinking and/or is not relieved by prescribed medicines
  • Throwing up more than 3 times a day
  • Diarrhea, 4 times in one day or diarrhea with lack of strength or a feeling of being dizzy
  • Blood in your stool
  • Abdominal pain that does not go away
  • Signs of possible liver problems: dark urine, pale bowel movements, bad stomach pain, feeling very tired and weak, unusual itching, or yellowing of the eyes or skin
  • Signs of allergic reaction: swelling of the face, feeling like your tongue or throat are swelling, trouble breathing, rash, itching, fever, chills, feeling dizzy, and/or feeling that your heart is beating in a fast or not normal way. Serious allergic reactions require immediate emergency treatment. If this happens, call 911 for emergency care.
  • If you think you may be pregnant

Reproduction Warnings 

  • Pregnancy warning: This drug can have harmful effects on the unborn baby. Clarithromycin should never be used by women who are pregnant or who could become pregnant while taking the drug. Let your doctor know right away if you think you may be pregnant.
  • Breastfeeding warning: It is not known if this drug passes into breast milk. For this reason, women should talk to their doctor about the risks and benefits of breastfeeding during treatment with this drug because this drug may enter the breast milk and cause harm to a breastfeeding baby.
  • Fertility warning: Fertility studies have not been done with this drug. Talk with your doctor or nurse if you plan to have children.

New June 2019

This patient information was developed by Via Oncology, LLC © 2019. This information is not intended to be used as a substitute for professional medical advice, diagnosis, or treatment. You should not rely entirely on this information for your health care needs. Ask your own doctor or health care provider any specific medical questions that you have.

CLIENT acknowledges that the Via Pathways and Via Portal are information management tools only, and that Via Oncology, LLC has not represented the Via Pathways or Via Portal as having the ability to diagnose disease, prescribe treatment, or perform any other tasks that constitute the practice of medicine. The clinical information contained in the Via Pathways and Via Portal are intended as a supplement to, and not a substitute for, the knowledge, expertise, skill, and judgment of physicians, pharmacists and other healthcare professionals involved with patient care at CLIENT facilities.