Sterile Water for Injection USP is a clear, colorless, odorless liquid. It is sterile, hypotonic, nonpyrogenic, and contains no bacteriostatic or antimicrobial agents. It is a diluent or solvent suitable for intravascular injection after first having been made approximately isotonic by the addition of suitable solute.

Sterile Water for Injection USP is also used as a diluent or solvent for other parenteral drugs. As such, it contributes to hydration when provided in parenteral drug and fluid therapy, after the introduction of suitable additives and/or mixture with suitable solutes to approximate isotonicity.