Usage
Used as an antimicrobial preservative in pharmaceutical excipients. Antimicrobial activity increases with carbon chain length, providing superior inhibition of molds and yeasts compared to methylparaben and ethylparaben. Widely applied in oral liquid preparations, topical ointments, creams, gels and suppositories. Often combined with methylparaben at different ratios (e.g., methylparaben:propylparaben = 4:1) to balance water solubility and antimicrobial efficacy. Also used for preservation in eye drops, syrups and other liquid formulations.