Guidelines for use of Avertin

Avertin (1.25 % tribromoethanol)

Many recipes are available for this anesthetic. Please use the recipe and dosages indicated below to avoid problems due to endotoxins, soap residues, breakdown products that are toxic, and anesthetic deterioration over time. Avertin is not appropriate for repeated anesthesia.

AVERTIN

The following recipe makes a 1.25% solution of Avertin. Avertin should be mixed using acid washed glass rinsed in distilled water. Glassware washed in soap leaves a residue that will potentially be toxic.

• Add the tribromoethanol to the butanol and dissolve by heating (40-50°C) and stirring.
• Add the PBS and continue to stir until butanol is totally dispersed.
• Sterilize via filtering through a 0.2 mm filter and decant into a sterile container (a filtering unit can be used).
• Measure pH (pH should be 7 to 7.4).
• Aliquot 2 ml volumes into sterile cryotubes and store at -20°C.
• Complete the final mix and sterilization as quickly as possible as the effectiveness of the mixture can be degraded by light and room temperature.

A dose of 0.025 ml/gram of body weight injected IP results in about 30 minutes of surgical anesthesia. If after five minutes the animal exhibits a paw pinch reflex an additional 0.05-0.1 ml may be injected. It is very important to inject Avertin IP and not SC as the latter results in delayed and extended induction period. Animals should be kept warm and closely monitored until they regain consciousness.

Dosage:

Approved: ____3/4/03____