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Bicillin L-A

Generic name: penicillin G benzathinePEN-i-SILL-in-G-BEN-za-theen ]
Drug class: Natural penicillins

Medically reviewed by on May 24, 2024. Written by Cerner Multum.

What is Bicillin L-A?

Bicillin L-A is an antibiotic that is used to treat many types of infections caused by bacteria, including strep or syphilis. This medicine is also used to prevent symptoms of rheumatic fever.

Bicillin L-A may also be used for purposes not listed in this medication guide.

Bicillin L-A side effects

Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).

Some side effects may occur if the medicine has been accidentally injected near a vein or nerve. Tell your doctor right away if you have:

Also call your doctor at once if you have:

Common side effects of Bicillin L-A 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.


Tell your doctor if you have ever had an allergic reaction to an antibiotic.

Before taking this medicine

You should not be treated with Bicillin L-A if you are allergic to penicillin.

Tell your doctor if you have ever had:

Tell your doctor if you are pregnant or breastfeeding.

How is Bicillin L-A given?

Bicillin L-A is injected into a muscle.

Read and follow all Instructions for Use. Ask your doctor or pharmacist if you need help.

Prepare an injection only when you are ready to give it. Call your pharmacist if the medicine has changed colors or has particles in it.

Do not reuse a needle or syringe. Place them in a puncture-proof "sharps" container and dispose of it following state or local laws. Keep out of the reach of children and pets.

Keep using this medicine even if your symptoms quickly improve. Skipping doses could make your infection resistant to medication. Bicillin L-A will not treat a viral infection (flu or a common cold).

Do not inject this medicine near or into an artery, vein, or nerve. Dangerous or fatal side effects could occur.

You may need tests after treatment to make sure your infection has completely cleared.

Store in the refrigerator, do not freeze.

What happens if I miss a dose?

Call your doctor for instructions if you miss a dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose may cause a seizure.

What should I avoid while receiving Bicillin L-A?

Avoid taking anti-diarrhea medicine without first asking your doctor. Diarrhea may be a sign of a new infection.

What other drugs will affect Bicillin L-A?

Tell your doctor about all your other medicines, especially:

This list is not complete. Other drugs may affect Bicillin L-A, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

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.