Many people have this mentality that bacteriostatic water and sterile water are the same thing, and that can bring disastrous results. Patients, athletes, healthcare workers and others use sterile solutions to help in medication delivery, injections, irrigation and other uses. Two sterile solutions that are commonly used are bacteriostatic water and sterile water. With patients having the autonomy to take medications at home at their own comfort, the education on these sterile solutions is crucial. Both have similar uses and are sterile but have drastically different demographics and indications. Let’s take a look at each one, where they differ, and where they overlap.

Sterile Water And Purity

Sterile water is purified water that has been distilled and brought to a pH between 5.0 to 7.0. There is no sort of preservative or antimicrobial agent added to it. Sterile water is available for injection use such as intravenous, intramuscular and subcutaneous. A separate formulation is used for irrigation such as washing, rinsing and diluting. Always double-check which mixture you have because you cannot interchange between these two formulations. Sterile water usually comes in single-unit doses and the reuse of units is prohibited. Due to the lack of antimicrobials, sterile water can easily be contaminated once exposed to surroundings and even yourself.

Bacteriostatic Water And Purity

Bacteriostatic water is a sterile form of water that has been brought to a pH between 4.5 to 7.0. It also is prepared with a bacteriostat, a compound used to prevent any bacterial growth. This bacteriostat is usually 0.9% benzyl alcohol. It is only used for injections such as intravenous, intramuscular and subcutaneous. Due to the bacteriostat, bacteriostatic water comes in a multi-dose formulation for multiple uses.

The Differences That Matter The Most

Let’s nail the major differences right from the start. As mentioned previously, sterile water only has distilled water and nothing else. Bacteriostatic water is water with benzyl alcohol. Immediately you can gauge which is appropriate based on allergies. If you have an allergy to benzyl alcohol, discontinue or avoid bacteriostatic water and opt for sterile water. Another difference is indications. Sterile water is labeled for both injections and irrigations whereas bacteriostatic water is only labeled for injections. Touched on earlier, another key difference is multiple uses. The absence of a bacteriostat in sterile water only allows for a one time use. Bacteriostatic water can be used multiple times for up to 28 days before the suggested disposal. This can come into play when preparing for traveling, budgeting monthly expenses and storage.

Medications that required diluting with water usually indicate on the bottle which water is preferred for use. Always use as directed on the label. A major difference between the two is the patient population. Bacteriostatic water is contraindicated, or forbidden, from being used in neonates, newborns in the first 28 days of their life. Another key difference is availability. Bacteriostatic water is very easy to manufacture while sterile water is an arduous process. There have been times when sterile water has been in short supply. It may be wise to always opt for bacteriostatic water if both water types are allowed for use.

Similarities That Overlap In Both Solvents

Both bacteriostatic water and sterile water are not used for straight injections, they have to be diluted with a drug or solvent. Using in such a matter can cause hemolysis or destruction of red blood cells. They both are nonpyrogenic meaning they won’t cause fever. Besides neonates, they both can be used for the rest of the population including pediatrics, adults and the geriatric community. Bacteriostatic water and sterile water can be used in intravenous, intramuscular and subcutaneous injections. They both are USP meaning they have an official monograph or documentation by the United States Pharmacopeia, both are not used for IV solutions. Due to the pH, a more apt solution for fluid replacement is normal saline or dextrose.

In Closing

This should hopefully shed some light on an easily confusing topic on which water to use. Definitely be educated on the similarities and differences and have confidence when purchasing. Using either in the proper conditions can provide extraordinary results.