Bacteriostatic water is frequently used in adults for mixing with injected medications. It is preferred to sterile water because the risk of contamination and subsequent infection is far lower. Additionally, because bacteriostatic water can be sold in multi-use vials, it is often cheaper than sterile water, which must be sold in single-use aliquots to ensure safety. Bacteriostatic Water is also commonly used for mixing with injected supplements, like human growth hormone. In most countries, bacteriostatic water can be purchased over the counter without the need for a prescription. It can easily be ordered online from any number of sources. It is also possible to produce bacteriostatic water at home through careful preparation of distilled water, followed by the application of bacteriostatic agents and careful filtration.
Sterile water for injection, whether it contains bacteriostatic benzyl alcohol or not, is prepared for diluting drugs, such as Human Growth Hormone. Hospira brand water for injection is prepared in a special plastic vial to prevent bacteria growth and contamination. Sterilized water via filtration or heating will not remove all contaminants and may not necessarily kill all bacteria, hence why Hospira products are in fact better as they are sterilized by numerous techniques for safe injection of diluted (sterile) drugs. Bacteriostatic Sodium Chloride for injection contains Sodium Chloride (NaCl) as well as a 0.9% Benzyl Alcohol for the dilution of specific drugs that require an acid additive.
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