Can SW, NS, and bacteriostatic water be used interchangeably to dilute medicines?

 

Sterile water, NS, and bacteriostatic water cannot be used interchangeably with each other. A thorough explanation is provided below. :)

Step-by-step explanation

We need to distinguish between SW for injection and bacteriostatic water for injection in the direction of dilution. A preservative is found in the bacteriostatic water. One cannot be replaced by the other. It is important to read the label and follow it exactly. Some sources use the abbreviation SW for sterile water for injection and NS for sterile normal saline solution for injection. In the dilution instructions on the bottle, bacteriostatic water is spelled out. Due to incompatibility, labels are strictly restricted to one choice of diluent. Incompatibility can lead to solution crystallization and/or clumping of the drug in the solution and can create a problem in the patient's tissue or circulation.