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Generic name: benzoyl peroxide and erythromycin topicalBEN-zoe-ill-per-OX-ide-and-er-ith-roe-MYE-sin ]
Drug class: Topical acne agents

Medically reviewed by on Jul 12, 2023. Written by Cerner Multum.

What is Benzamycin?

Benzoyl peroxide has an antibacterial effect. It also has a mild drying effect that allows excess oils and dirt to be easily washed away.

Erythromycin is an antibiotic. Erythromycin topical prevents bacteria from growing on the skin.

Benzamycin (for the skin) is a combination medicine used to treat acne.

Benzamycin may also be used for purposes not listed in this medication guide.

Benzamycin side effects

Benzoyl peroxide can cause a rare but serious allergic reaction or severe skin irritation. These reactions may occur just a few minutes after you apply the medicine, or within a day or longer afterward.

Stop using Benzamycin and get emergency medical help if you have any of these signs of an allergic reaction: hives, itching; difficult breathing, feeling light-headed; swelling of your face, lips, tongue, or throat.

This medicine may cause serious side effects. Stop using this medicine and call your doctor at once if you have:

Common side effects of Benzamycin may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


This medicine can cause a rare but serious allergic reaction or severe skin irritation. Stop using this medicine and get emergency medical help if you have: hives, itching; difficult breathing, feeling light-headed; or swelling of your face, lips, tongue, or throat.

Before taking this medicine

You should not use Benzamycin if you are allergic to benzoyl peroxide or erythromycin (Akne-Mycin, Eryderm, Erythrocin, Pediazole, and others).

FDA pregnancy category C. It is not known whether Benzamycin will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medicine.

It is not known whether benzoyl peroxide and erythromycin topical passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

How should I use Benzamycin?

Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Wash your hands before and after applying this medication.

Clean and dry the area to which you will apply the medication. Benzamycin is usually applied twice daily in the morning and evening. Follow your doctor's directions.

Avoid getting this medicine in your eyes, mouth, or nose (or in the creases of your nose), or on your lips. If it does get into any of these areas, wash with water. Do not apply this medicine to sunburned, windburned, dry, chapped, irritated, or broken skin.

Do not cover the treated skin area after applying Benzamycin. Doing so could cause too much medicine to be absorbed by the body and could be harmful.

It may take several weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Apply the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the dose you missed and apply only the next regularly scheduled dose.

What happens if I overdose?

An overdose of Benzamycin is not expected to be dangerous. Seek emergency medical attention or call the Poison Help line at 1-800-222-1222 if anyone has accidentally swallowed the medication.

What should I avoid while taking benzoyl peroxide and erythromycin topical?

Do not use Benzamycin on sunburned, windburned, dry, chapped, or irritated skin. It could make these conditions much worse. Also avoid using Benzamycin on wounds or on areas of eczema. Wait until these conditions have healed before using this medicine.

Avoid using skin products that can cause irritation, such as harsh soaps, shampoos, or skin cleansers, hair coloring or permanent chemicals, hair removers or waxes, or skin products with alcohol, spices, astringents, or lime.

Avoid using other medications on the areas you treat with Benzamycin unless your doctor tells you to.

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, stop using Benzamycin and call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.

Avoid exposure to sunlight or tanning beds. This medication can make you sunburn more easily. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

Avoid using sunscreen containing PABA on the same skin treated with Benzamycin, or skin discoloration may occur.

Benzoyl peroxide can bleach hair or fabrics. Do not let this medicine come into contact with clothing, hair, or colored towels or bed linens.

What other drugs will affect Benzamycin?

Do not use Benzamycin during treatment with tretinoin (Retin-A). The combination could lead to severe skin irritation.

It is not likely that other drugs you take orally or inject will have an effect on topically applied benzoyl peroxide and erythromycin. But many drugs can interact with each other. Tell each of your health care providers about all medicines you use, including prescription and over-the-counter medicines, vitamins, and herbal products.

More about Benzamycin (benzoyl peroxide / erythromycin topical)

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Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.