Randomized, double-blind, placebo-controlled, dose-escalation study: Investigation of the safety, pharmacokinetics, and antihyperalgesic activity of l-4-chlorokynurenine in healthy volunteers.

Background And Aims: Neuropathic pain is a significant medical problem needing more effective treatments with fewer side effects. Overactive glutamatergic transmission via N-methyl-d-aspartate receptors (NMDARs) are known to play a role in central sensitization and neuropathic pain. Although ketamine, a NMDAR channel-blocking antagonist, is often used for neuropathic pain, its side-effect profile and abusive potential has prompted the search for a safer effective oral analgesic.