Anesthesia in the mouse using a combination of ketamine and promazine

An anesthetic combination of ketamine and promazine was tested in 25 male and 25 female mice of each of two strains. The mean induction time was 5 minutes for the C57BL/6We mouse and 8 minutes for the DBA/2We mouse. No sex differences were observed. The mean duration time was 45 minutes for the C57BL/6We male, 53 minutes for the C57BL/TWe female, 29 minutes for the DBA/2We male, and 35 minutes for the DBA/2We female. The mean recovery time was 39 minutes for the C57BL/6We male, 38 minutes for the C57BL/6We female, 21 minutes for the DBA/2We male, and 24 minutes for the DBA/2We female. The drug combination provided effective anesthesia for these strains of the laboratory mouse for a period of 30--50 minutes after a single intramuscular injection.