Medicinehospital

Penicillin G

An injectable penicillin antibiotic given for bacterial infections.

Clinical information

Common side effects

allergic reactions such as rash and hives
feeling sick and vomiting
stomach upset
sore mouth or black hairy tongue
pain at the injection site

Cautions

serious, occasionally fatal allergic reactions — tell your doctor about penicillin allergy
antibiotic-related C. difficile diarrhoea can occur, even months later
very high IV doses can upset potassium and cause neurological effects

Interactions

tetracyclines, erythromycin and similar antibiotics (may blunt its effect)
probenecid (prolongs penicillin levels)
aspirin, some diuretics (prolong penicillin in the blood)

Pregnancy: no harm shown — use only if clearly needed

Reference information, not medical advice — always follow your doctor or pharmacist. Source: DailyMed, dailymed.nlm.nih.gov, penicillin G potassium label, setid 9e58122f-5c75-4905-a774-d3a4dae4ff8c (accessed 2026-08-16)

Approved brands & formulations12

Brand name	Dosage form	Strength	Importer	Category
Benzyl Penicillin 5Lac Inj	Parenteral ( Injection )	50000 iu/5ml	authorized medicine importers	hospital
Penicillin Benzathine	Parenteral ( Injection )	2400000 units	MFDA designated importers with Pre Authorization approval before import	hospital
Penicillin Benzathine	Parenteral ( Injection )	600000 units	MFDA designated importers with Pre Authorization approval before import	hospital
Penicillin Benzathine	Parenteral ( Injection )	1200000 units	MFDA designated importers with Pre Authorization approval before import	hospital
Penicillin Benzyl	Parenteral ( Injection )	100000 iu/5ml	MFDA designated importers with Pre Authorization approval before import	hospital
Penicillin Benzyl	Parenteral ( Injection )	50000 iu/5ml	MFDA designated importers with Pre Authorization approval before import	hospital
Penicillin G Potassium	Tablet	400 mg	—	POM
Penicillin G Procaine	Parenteral ( Injection )	100000iu/ml , 300000iuml	MFDA designated importers with Pre Authorization approval before import	hospital
Penidure La 24	Parenteral ( Injection )	2400000 units	authorized medicine importers	hospital
Penidure La 24	Parenteral ( Injection )	2400000 units	authorized medicine importers	hospital
Penidure La 6	Parenteral ( Injection )	600000 units	authorized medicine importers	hospital
Penidure La 6	Parenteral ( Injection )	600000 units	authorized medicine importers	hospital