MedicinehospitalEssential

Benzathine Benzylpenicillin

A long-acting penicillin antibiotic given by injection into a muscle.

Clinical information

Common uses

streptococcal throat and upper respiratory infections
syphilis, yaws, bejel and pinta
preventing rheumatic fever coming back

Common side effects

allergic reactions such as rash or hives
injection site pain, swelling or lumps
Jarisch-Herxheimer reaction when treating syphilis

Cautions

must never be injected into a vein — has caused deaths
not for people with previous penicillin allergy
severe skin reactions — stop immediately if suspected

Interactions

tetracycline (may counteract penicillin — avoid together)
probenecid (raises and prolongs penicillin levels)

Reference information, not medical advice — always follow your doctor or pharmacist. Source: DailyMed, dailymed.nlm.nih.gov, BICILLIN L-A (penicillin G benzathine) label, setid 012d46f1-d0a0-4676-a879-cd320297ab16 (accessed 2026-08-16)

Approved brands & formulations2

Brand name	Dosage form	Strength	Importer	Category
Benzathine Benzylpenicillin	Parenteral ( Injection )	1,200,000 Units	MFDA designated importers with Pre Authorization approval before import	hospital
Benzathine Benzylpenicillin	Parenteral ( Injection )	powder for injection: 1.44 g benzylpenicillin (=2.4 million IU), in 5-ml vial	MFDA designated importers with Pre Authorization approval before import	hospital