[Intravenous S-+-ketamine for treatment of visceral pain in the final phase].

Ketamine is a hypnotic pharmacon with high analgesic potency. Ketamine is an agent blocking NMDA-receptors and involves opioid receptors, the voltage-gated sodium-channel, cholinergic receptors and the monoaminergic descending inhibitory pathways. Besides its influence in chronification of pain, NMDA-R is crucial in induction and maintainance of visceral pain, attentional perceptual processes and emotional valuation of pain. The analgesic potency of S-+-Ketamine doubles racemic Ketamine's analgesic potency. Thus the incidence of CNS-side effects ought to be reduced to 50% in equianalgesic dosages. Evidence supports the assumption that continuous infusion of S-+-Ketamine 2.5-5 mg/hour is effective in treating visceral pain of high intensity. In the presence of chronic pain states the effect ought to be more marked. There is evidence that the probability of psychotomimetic side effects does not exceed 10%. The rate of side effects can further be minimized through careful titration and prophylaxis (or treatment) with Diazepam 1 mg i.v.