Erythromycin is used to treat a wide variety of bacterial infections. It may also be used to prevent certain bacterial infections. Erythromycin is known as a macrolide antibiotic. It works by stopping the growth of bacteria.

This antibiotic treats or prevents only bacterial infections. It will not work for viral infections (such as common cold, flu). Using any antibiotic when it is not needed can cause it to not work for future infections.

This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.

This drug may also be used for a certain type of stomach condition involving slowed digestion (gastroparesis).

Take this medication by mouth as directed by your doctor. This medication is best absorbed when taken on an empty stomach. If nausea occurs, you may take it with food or milk. Swallow the medication whole. Do not crush, chew, or break it.

The dosage and length of treatment are based on your medical condition and response to treatment. Children's dosage is also based on age and weight.

For the best effect, take this antibiotic at evenly spaced times. To help you remember, take this medication at the same time(s) every day.

If you are using this medication to treat an infection, continue to take this medication until the full prescribed amount is finished, even if symptoms disappear after a few days. Stopping the medication too early may result in a return of the infection. Tell your doctor if your condition lasts or gets worse.

If you are taking this medication to prevent certain bacterial infections, take it exactly as directed by your doctor. Do not stop taking the medication without your doctor's approval.

Nausea, vomiting, diarrhea, stomach pain/cramping, and loss of appetite may occur. Taking this medication with food may lessen these symptoms. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

• signs of liver disease (such as nausea/vomiting that doesn't stop, yellowing eyes or skin, dark urine, severe stomach/abdominal pain)
• unusual tiredness
• muscle weakness
• trouble speaking
• blurred vision
• drooping eyelids
• hearing loss

Get medical help right away if you have any very serious side effects, including:

• severe dizziness
• fainting
• fast/irregular heartbeat

This medication may rarely cause a severe intestinal condition due to a bacteria called C. difficile. This condition may occur during treatment or weeks to months after treatment has stopped. Tell your doctor right away if you develop:

• diarrhea that doesn't stop
• abdominal or stomach pain/cramping
• blood/mucus in your stool

If you have these symptoms, do not use anti-diarrhea or opioid products because they may make symptoms worse.

Use of this medication for prolonged or repeated periods may result in oral thrush or a new yeast infection. Contact your doctor if you notice white patches in your mouth, a change in vaginal discharge or other new symptoms.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking erythromycin, tell your doctor or pharmacist if you are allergic to it; or to other macrolide antibiotics (such as azithromycin, clarithromycin); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• liver disease
• kidney disease
• a certain type of muscle disease (myasthenia gravis)

Erythromycin may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.

The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using erythromycin, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions:

• certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG)
• family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death)

Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using erythromycin safely.

Erythromycin may cause live bacterial vaccines (such as typhoid vaccine) to not work well. Tell your health care professional that you are using erythromycin before having any immunizations/vaccinations.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Some erythromycin products may contain sodium. Ask your doctor or pharmacist for more information if you are on a salt-restricted diet or if you have a condition that could be worsened by an increase in salt intake (such as heart failure).

Older adults may be more sensitive to the side effects of this drug, especially hearing loss and QT prolongation (see above).

Tell your doctor if you are pregnant before using this medication.

This medication passes into breast milk. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

A product that may interact with this drug is:

• digoxin

Many drugs besides erythromycin may affect the heart rhythm (QT prolongation), including amiodarone, dofetilide, pimozide, procainamide, propafenone, quinidine, sotalol, among others.

Other medications can affect the removal of erythromycin from your body, which may affect how erythromycin works. Examples include azole antifungals (such as itraconazole, ketoconazole), certain calcium channel blockers (such as diltiazem, verapamil), certain anti-seizure medications (such as carbamazepine, phenytoin), among others.

Erythromycin can slow down the removal of other drugs from your body, which may affect how they work. Examples of affected drugs include bromocriptine, colchicine, certain benzodiazepines (such as midazolam, triazolam), eletriptan, ergot alkaloids (such as ergotamine, dihydroergotamine), certain drugs to treat erectile dysfunction-ED or pulmonary hypertension (such as sildenafil, tadalafil), certain "statin" drugs (such as lovastatin, simvastatin), vinblastine, among others.

This medication may interfere with certain lab tests (such as urine tests), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

This medication has been prescribed for your current condition only. Do not use it later for another infection unless your doctor tells you to.

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.