benzylpenicillin sodium: clinical use

Prescribing considerations

• Confirm the intended salt, route and product because injectable sodium, benzathine and procaine salts are not interchangeable.
• Base use on infection severity, microbiology where available, local susceptibility and antimicrobial policy.
• Review renal function, age-related clearance, hepatic disease, heart failure and total sodium exposure.
• Use freshly reconstituted solution and avoid sodium-containing diluents where sodium overload is a concern.
• Watch for superinfection and antibiotic-associated colitis during or after treatment.

Contraindications and cautions

• Known hypersensitivity to penicillins or an ingredient of the preparation
• Avoid after a severe previous hypersensitivity reaction to another beta-lactam; use caution with a non-severe beta-lactam allergy history

Monitoring

• Observe for immediate hypersensitivity after administration.
• Monitor renal function and neurological status where accumulation is possible.
• Consider electrolytes, full blood count and renal function with substantial exposure or prolonged treatment.
• Assess severe or persistent diarrhoea for antibiotic-associated colitis.

Clinical pharmacology

A bactericidal, beta-lactamase-sensitive penicillin that inhibits bacterial cell-wall biosynthesis. It is cleared rapidly, predominantly by renal tubular secretion; probenecid reduces this clearance.

Formulation and product differences

• The product is a sterile, water-soluble powder for intramuscular or intravenous administration and contains no listed excipients.
• It contains clinically relevant sodium, which should be included when assessing total sodium burden.
• Benzathine and procaine benzylpenicillin are longer-acting intramuscular preparations with different indications and must not be substituted for benzylpenicillin sodium.

Injection

Route: Parenteral

Strengths: 600 mg, 1200 mg