Ketamine anaesthesia following premedication of rabbits with vitamin C

The effects of vitamin C on ketamine anesthesia was studied. In normal rabbits the onset and duration of ketamine induced anesthesia were 6.0 +/- 0.5 and 36.0 +/- 0.9 min, respectively. Pre-treatment of rabbits with 30, 60 and 240 mg/kg, i.m. of vitamin C followed by ketamine 40 mg/ kg i.m. resulted in significant (p < 0.05) decrease in the onset and increase in duration of ketamine anesthesia to 5.0 +/- 0.06 and 37.0 +/- 0.7; 4.0 +/- 0.5 and 39.0 +/- 0.6; 2.0 +/- 2.3 and 44.0 +/- 0.8 min, respectively. There was also significant (p < 0.05) decrease in the heart rates in the animals treated with vitamin C and ketamine combinations. Serum analysis showed a significant (p < 0.05) increase in blood glucose. The observed decreased in serum calcium and phosphorous following ketamine injection was prevented by pretreatment with vitamin C. These results suggest that vitamin C at higher doses could potentiate ketamine anesthesia in rabbits.