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Erythromycin

Antibiotic

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What is erythromycin?

Erythromycin (also called Ery-Tab®, E-Mycin®, EES®, PCE®, and ERYC®) is used to prevent or treat infections. It is also taken by mouth to improve stomach emptying time and how well the intestines work. It is applied to the skin to treat acne. Erythromycin is available in many different forms, brands, and strengths, including the following:

  • Capsules, tablets (some are extended-released), and liquid suspensions, all of which are taken by mouth
  • Clear liquid to be given by vein (IV)
  • Eye ointment
  • Skin ointment and solution
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Possible side effects

  • Nausea, vomiting
  • Diarrhea
  • Rash
  • Loss of appetite
  • Headache
  • Stomach pain
  • Indigestion
  • Ringing in ears, hearing loss (usually with IV)
  • Pain at injection site (IV)
  • Abnormal liver function tests, which may cause yellowing of eyes or skin and dark yellow or brown urine (especially with the estolate salt)
  • These are the most common side effects, but there may be others. Please report all side effects to the doctor or nurse.

Symptoms of an allergic reaction include: rash, hives, itching, chills, fever, headache, muscle ache, shortness of breath, coughing, tightness in the throat, swelling of the face or neck.

Not all patients who take erythromycin will experience these side effects. Common side effects are bolded, but there may be others. Please report all suspected side effects to your doctor or pharmacist.

Find more information on side effects.

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Possible late effects

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Tips for patients and families

Be sure to discuss all questions and instructions with your doctor or pharmacist. 

  • Before taking erythromycin, tell your doctor if you have had an allergic reaction to erythromycin in the past.
  • If signs of an allergic reaction occur, tell your doctor right away. Signs of an allergic reaction include rash, itching, trouble swallowing, or swelling of the face, lips, or tongue.
  • While taking erythromycin, if you have yellowing of the eyes or skin, yellow-brown urine, or severe or watery diarrhea, tell your doctor right away.
  • Finish all doses of this medicine as your doctor told you, even if you think your condition is better. Do not stop taking this medicine unless your doctor tells you to do so.
  • Erythromycin may affect the way other medicines work. These medicines include: warfarin, theophylline, cyclosporine, phenytoin, carbamazepine, ranitidine, omeprazole, triazolam, astemizole, ergotamine, ritonavir, zidovudine, fluconazole, valproic acid, birth control medicines, and digoxin.
  • Always tell your doctor if you are taking these medicines, or if you start taking any new medicine while taking erythromycin.
  • While taking erythromycin, birth control medicines that contain estrogen may not work well. Use a second birth control method for at least one (1) month after taking erythromycin.
  • Follow these guidelines if you are using the eye ointment:
    • Wash your hands before and after use.
    • Tilt your head back and pull your lower eyelid down with your index finger to form a pouch. Squeeze the end of the tube to apply a thin layer of the ointment inside the lower eyelid.
    • Close the eye gently to spread the ointment over the eye.
    • Try not to touch the end of the tube to your eye, fingertips, or any other surface.
    • Your vision may blur for a few minutes after applying the ointment.
    • Even if your eye infection seems better after a few doses, apply all the doses of the ointment that your doctor prescribed.
    • If you have burning or stinging in the eye, continued blurred vision, or redness and swelling of the eye, tell your doctor right away.

Drug at Home:

  • Some brands of erythromycin must be taken on an empty stomach, one (1) hour before meals or 2 hours after a meal. Other brands can be taken with or without food. Ask your pharmacist if you can take your medicine with food.
  • Shake the liquid well before you take it. Use an oral syringe or medicine cup to be sure you are taking the correct amount.
  • Most brands of erythromycin liquid medicines should be kept in the refrigerator. Ask your pharmacist if you need to keep your medicine in the refrigerator.
  • Discard the liquid medicine after the date printed on the label. Throw away any unused eye ointment when it reaches the expiration date.
  • Store all tablets and capsules at room temperature in a dry place.
  • Do not crush, cut, or chew the extended-release tablets or capsules. Swallow them whole.
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Always check the medication label. Many medicines look the same. Do not take any new medicine, including over-the counter medicines or supplements, without checking with your doctor or pharmacist. Talk to your doctor or pharmacist about what to do in the case of a missed dose, allergic reaction, or medical emergency. 

This information is not intended to be a complete guide and is not a substitute for talking with your provider. Medicine names, appearance, formulas, or availability may vary by clinic location. Always follow the instructions given by your care team.

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