The aim of the present study was to explore the effect of three selective sedative/tranquilizer drugs i.e. Xylazine(XZ), Acepromazine(AC), and Diazepam(DZ) on normal physiological parameters such aspulse, respiration, body temperature and serum glucose.All the three drugs i.e. Xylazine, Acepromazine, and Diazepam were used at the dose rate of 8mg/kg, 5 mg/kgand diazepam1mg/kg respectivelythrough intramuscular route(I.M.)in six healthy rabbits of non-descriptive Before administration of drugs all physiological parameters were recordedPulse, respiration and body temperature shows significant (0.05) decrease after administration of these drugs. Maximum decrease in the pulse rate was recorded at 60, 30 and 45 minutes and were returned to its normal at 150, 135 and 135 minutes with XZ, AC and DZ Low respiratory rate was noted at 45, 30 and 75 minutes and were returned to the non-significant level at 105, 90 and 135 minutes with XZ, AC and DZ Body temperature decreased to its maximum at 45, 30 and 60 minutes and returned to its normal at 120, 120 and 135 minutes after administration of XZ, AC and DZ Onset of sedation started at 83±0.30, 6.16±0.47 and 3.83±0.30 minutes with XZ, AC and DZ Significant difference were found in XZ and AC, DZ and AC at 0.05 but there was no significant difference between XZ and Total duration of sedation was 101.17±1.07, 00±1.87 and 90.00±1.29 with XZ, AC and DZ respectively.XZ and DZ significantly (P< 0.05) increase serum glucose level while AC have no significant effect on serum glucose From the overall finding all the three drugs were were found safe for rabbits but XZ shows the best results.