Abstract
The influence of repeated injections of ketamine hydrochloride was studied using 12 dogs. They were anesthetized a total of 10 times. They were injected intervenously every three days. Six dogs were injected with 5 mg/kg each time. The other six were injected with 10 mg/kg each time.
The following results were obtained : Dogs of both groups seemed to develop a tolerance to this agent for the following three reasons. 1. The time needed to recover their pain sensation, 2. the time needed for rising, 3. the time needed for ambulation steadily decreased throughout the testing period. Blood pressure, heart rate, respiration rate and body temperature were not affected by the repeated anesthesia, and no serious side effects were encountered. Dogs remained in good health throughout the experimental study. It seems likely that the risk of repeated injections with ketamine is minimal but we must take into account the development of a tolerance to the agent and the number, frequency and dose of the dosages.
