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Solvents & reconstitution

Bacteriostatic Water

Also known as: Bacteriostatic water for injection · BAC water

A preserved sterile water used as a diluent to reconstitute lyophilized peptides; it is a solvent, not a therapeutic.

Bacteriostatic Water at a glance

NameBacteriostatic Water
Also known asBacteriostatic water for injection, BAC water
CategorySolvents & reconstitution
TypeAmino / injectable
SequenceSterile water containing 0.9% benzyl alcohol as a preservative.
Typical doseNo therapeutic dose - volume chosen to reach a desired concentration
FrequencyNot applicable
RouteDiluent (mixed into a powder vial)
Half-lifeNot applicable - it is a solvent, not an active compound.

Overview

Bacteriostatic water is sterile water for injection with 0.9% benzyl alcohol added as a bacteriostatic preservative. The preservative lets a vial be entered multiple times over a limited period without supporting bacterial growth, which is why it is commonly chosen for reconstituting multi-use peptide vials.

How it’s thought to work

  • Serves as the liquid vehicle that dissolves a lyophilized powder.
  • The 0.9% benzyl alcohol inhibits bacterial growth in an entered vial.
  • Allows repeated withdrawals from a multi-dose vial within its in-use window.
  • Has no pharmacological action of its own on the target condition.

Researched uses

  • Reconstituting lyophilized peptides and other powders
  • Preparing multi-use injectable vials
  • General diluent for compatible medications
  • Laboratory and research dilution

Commonly cited protocol

Typical doseNo therapeutic dose - volume chosen to reach a desired concentration
FrequencyNot applicable
RouteDiluent (mixed into a powder vial)
NotesOften avoided in neonates and in large volumes due to benzyl alcohol content.

Reconstitution

This item is itself the diluent. The volume added to a powder sets the final concentration (for example, 2 mL into a 5 mg vial yields 2.5 mg/mL). Its benzyl alcohol preservative makes it suited to multi-use vials.

Cautions

  • A medical solvent, not a therapeutic agent.
  • Benzyl alcohol can be unsuitable for neonates and for very large cumulative volumes.
  • Maintain aseptic technique and observe in-use dating.
  • Educational information only, not medical advice.

Bacteriostatic Water FAQ

What is Bacteriostatic Water?

A preserved sterile water used as a diluent to reconstitute lyophilized peptides; it is a solvent, not a therapeutic.

How does Bacteriostatic Water work?

Serves as the liquid vehicle that dissolves a lyophilized powder. The 0.9% benzyl alcohol inhibits bacterial growth in an entered vial. Allows repeated withdrawals from a multi-dose vial within its in-use window. Has no pharmacological action of its own on the target condition.

What is Bacteriostatic Water used for?

Reconstituting lyophilized peptides and other powders; Preparing multi-use injectable vials; General diluent for compatible medications; Laboratory and research dilution.

What is a typical Bacteriostatic Water dose?

No therapeutic dose - volume chosen to reach a desired concentration, Not applicable, Diluent (mixed into a powder vial). This is a commonly cited figure for context only, not medical advice.

How do you reconstitute Bacteriostatic Water?

This item is itself the diluent. The volume added to a powder sets the final concentration (for example, 2 mL into a 5 mg vial yields 2.5 mg/mL). Its benzyl alcohol preservative makes it suited to multi-use vials.

What is the half-life of Bacteriostatic Water?

Not applicable - it is a solvent, not an active compound.

Related solvents & reconstitution peptides

⚠️ Educational reference only — not medical advice. These compounds are largely research chemicals not approved for human use in most countries. Nothing here is a recommendation to obtain or administer any substance. Consult a qualified clinician.