penicillin G benzathine (Bicillin L-A)

Pharmacy Author:
Medical and Pharmacy Editor:

GENERIC NAME: penicillin G benzathine injectable suspension

BRAND NAME: Bicillin L-A

DRUG CLASS AND MECHANISM: Penicillin G benzathine (Bicillin L-A) is a penicillin antibiotic that is given by deep intramuscular injection. Penicillin G benzathine kills susceptible bacteria by inhibiting the synthesis or formation of bacterial cell wall. It is thought to preferentially bind to specific penicillin-binding proteins (PBPs) found inside the bacterial cell wall. The end result of the inhibition of bacterial cell synthesis is cell lysis and the death of the susceptible bacteria.

Penicillin G benzathine has poor solubility and is therefore very slowly released from the site of injection. In the blood, penicillin G benzathine is broken down to penicillin G. Penicillin G benzathine formulation is released and absorbed slowly to allow for a more prolonged duration of action (drug works slowly over an longer period of time).


GENERIC AVAILABLE: Not available in the US

PREPARATIONS: Penicillin G benzathine injectable suspension: 1 ml (600,000 units per syringe), 2 ml (1,200,000 units per syringe), and 4 ml (2,400,000 units per syringe).

STORAGE: Suspension should be stored in a refrigerator, between 2 C and 8 C (36 F and 86 F).


Intramuscular penicillin G benzathine is used to treat the following conditions:

Medically Reviewed by a Doctor on 11/24/2014

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Pill Finder Tool

Need help identifying pills and medications?
Use the pill identifier tool on RxList.

Back to Medications Index

Health Solutions From Our Sponsors