Pharmacodynamics and reversal of benzodiazepine-ketamine ataranalgesia.

We describe the combined use of ketamine with benzodiazepines, which produces a state of ataranalgesia. From our investigation of the combination of ketamine with three such drugs--diazepam, flunitrazepam and midazolam--we conclude that the ketamine-midazolam sequence is the best combination in terms of preservation of physiological homeostasis and recovery time. In addition, we describe the reversal of ketamine-diazepam ataranalgesia by the new cholinergic agonist, 4-aminopyridine.