Antihyperalgesic and analgesic properties of the N-methyl-d-aspartate (NMDA) receptor antagonist neramexane in a human surrogate model of neurogenic hyperalgesia

Abstract NMDA-receptors are a major target in the prevention and treatment of hyperalgesic pain states in neuropathic pain. However, previous studies revealed equivocal results depending on study design and efficacy parameters. We tested the analgesic (generalized reduction of generation and processing of nociceptive signalling) and anti-hyperalgesic (prevention of central sensitization) properties of the NMDA-receptor antagonist neramexane and the potassium channel opener flupirtine in the intradermal capsaicin injection model. Furthermore, we tested the effect on pain summation (wind up). Eighteen healthy subjects received either a single dose of neramexane (40 mg p.o.), flupirtine (100 m…