Bacteriostatic Water
Sterile water containing 0.9% benzyl alcohol preservative, used to reconstitute lyophilised peptides for multi-dose use. The preservative allows multiple withdrawals over up to 28 days, unlike preservative-free sterile water which should be used within 24 hours. Not suitable for neonates.
Technical Context
Bacteriostatic water USP: water for injection containing 0.9% (w/v) benzyl alcohol as an antimicrobial preservative. Benzyl alcohol mechanism: disrupts bacterial cell membrane integrity, inhibiting growth of most common contaminants. Multi-dose vial usage: each withdrawal introduces potential contaminants from the needle, stopper, and environment — benzyl alcohol prevents their proliferation. The 28-day multi-use limit is based on preservative efficacy testing demonstrating adequate antimicrobial activity for this duration under normal use conditions. Contraindications: benzyl alcohol is contraindicated in neonates and premature infants (associated with gasping syndrome — metabolic acidosis, neurological deterioration, potentially fatal; due to immature hepatic metabolism). For these populations, preservative-free sterile water for injection is required. Benzyl alcohol allergy (rare) is another contraindication. Storage: room temperature (15-30°C), protect from freezing.