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What is it?

Erythromycin is an antibiotic used to treat mild to moderate bacterial infections.

How to take this medication:

This medication should be taken on an empty stomach (at least 30 minutes and preferably 2 hours before or after a meal).

Antibiotics work best when the amount of medicine in your body is kept at a constant level. If you need to take more than one dose, be sure to evenly space out the doses (ex: 7am and 7pm). Continue to take this medication until it is all gone even if symptoms go away after a few days. Not finishing the medication may allow bacteria to keep growing.

Do NOT take this medication if you:

Are allergic to erythromycin or any of the non-medicinal ingredients.

Have had a previous reaction to erythromycin.

Are taking any of the following medications:

  • Dihydroergotamine, ergotamine (for migraine)
  • Cisapride (for stomach problems)
  • Astemizole & terfenadine (antihistamines for allergies)
  • Pimozide (for psychiatric disorders)

Tell your health care provider if you:

Suffer from liver disease.

Suffer from myasthenia gravis (a condition caused by muscle weakness, difficulty chewing and swallowing, slurred speech).

Are pregnant and/or breastfeeding.

Side Effects:

This medication may cause some minor and temporary side effects such as stomach cramping and discomfort. Contact your health care provider right away if you experience any symptoms of liver problems such as:

  • Nausea and vomiting
  • Severe stomach pain
  • Diarrhea
  • Yellowing of the skin and eyes
  • Itchy skin rash
  • Hearing problems
  • Confusion
  • Hallucinations
  • Dizziness and balance problems
  • Seizure

If you develop diarrhea that becomes severe and watery or does not go away, stop taking this medication and call your health care provider. This could be a sign of a serious medical problem. Do not take over-the-counter medications to treat diarrhea without first talking with your health care provider.

Stop taking this medication and call your health care provider if you experience an irregular heart beat (palpitations).

Allergic reactions to erythromycin are rare, but these reactions can be very serious if not treated right away. If you experience any of the following symptoms, seek medical attention right away:

  • Trouble breathing
  • Swelling in the face, mouth and neck
  • Severe skin rash, hives or blisters

Drug interactions:

Tell your health care provider of all the over-the-counter and prescription medications you are taking, including:

  • Alfentanil, midazolam and triazolam (sedatives which may be given before an operation)
  • Atorvastatin, lovastatin (for reducing blood cholesterol)
  • Carbamazepine, hexobarbital, phenytoin (for epilepsy)
  • Chloramphenicol, clindamycin and lincomycin (for infections)
  • Cyclosporin (for prevention of rejection after graft or organ transplant)
  • Digoxin and quinidine (for heart conditions)
  • Oral anticoagulants (for preventing blood clots)
  • Theophylline (for breathing problems)

Missed dose:

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


Store tablets at room temperature, in a tightly closed container. Do not allow medication to freeze. Keep out of reach and sight of children.

Points to remember:

This medication is meant to treat your current infection only.

If you are in a sexual relationship, your partner will also need treatment for this infection. If your partner is not treated, they can re-infect you with the same bacteria. Talk to your health care provider about treatment for your sexual partner.

Sometimes this medication doesn’t always get rid of the infection. It is important that you get follow-up testing after taking this medication to make sure that your infection is gone. Make a plan with your health care provider for follow-up testing.