Water for injection

• BPWater for Injections
• JPWater for Injection
• Ph. Eur.Water for Injections
• USP–NFWater for Injection

Aqua ad iniectabilia; WFI; water for injections in bulk; sterilised water for injections

Water · [7732-18-5]

UNII 059QF0KO0R · PubChem CID 962

H2O · 18.02

Solvent, humectant

Typical concentrations: — · Dosage forms: Sterile (parenteral/ophthalmic)

The vehicle and solvent for parenteral products and the water used in their manufacture, including final rinsing of containers and equipment that contact parenteral products. Sterile water for injections in final containers is used to reconstitute or dilute powders and concentrates for injection.

A clear, colourless, odourless and tasteless liquid. Water for injections in bulk is purified water of high chemical and microbiological quality with a specified endotoxin limit; it is not necessarily sterile until it has been filled and sterilised.

Conductivity

not more than 1.3 µS/cm at 25 °C (USP stage 1); Ph. Eur. bulk limit 1.1 µS/cm at 20 °C

Total organic carbon

not more than 0.5 mg/L (500 ppb)

Bacterial endotoxins

less than 0.25 EU/mL

Microbial count

action level 10 CFU per 100 mL (bulk water)

Boiling point

100 °C

Chemically stable, but bulk water is prone to microbial growth and absorbs carbon dioxide and other gases. To control contamination it is usually stored and circulated hot (typically above 70 °C) in a sanitary loop, or used within a short time of production.

Reacts with drugs and excipients that are susceptible to hydrolysis, and with water-reactive materials such as alkali metals and some anhydrous salts.

Produced from water that complies with drinking-water standards, or from purified water, traditionally by distillation in a neutral glass, quartz or suitable metal still. USP and, since 2017, Ph. Eur. also allow non-distillation processes, typically reverse osmosis combined with other techniques such as electrodeionisation and ultrafiltration, provided they give equivalent quality.

Water itself is non-toxic, but large intravenous volumes of water without added solute are hypotonic and cause haemolysis; sterile water for injections should therefore not be infused directly in large volumes. Endotoxin control is essential to avoid pyrogenic reactions.

Hot-water systems present a burn hazard. Generation, storage and distribution systems must be designed, validated and monitored to maintain quality, with regular sampling for conductivity, TOC, microbial count and endotoxins.

Included in the FDA Inactive Ingredient Database (injections and other sterile preparations) and in parenteral medicines licensed worldwide. Requirements for its production are set out in the pharmacopoeias and in GMP guidance.

Purified water; sterile water for injection; bacteriostatic water for injection; sterile water for irrigation; sterile water for inhalation.

Bacteriostatic water for injection, which contains an antimicrobial preservative such as benzyl alcohol, must not be used in neonates or for large-volume use. Pharmacopoeial requirements for bulk water and for sterile packaged water differ, so the appropriate monograph must be applied.