[Analgesic effect of the selective noradrenaline reuptake inhibitor reboxetine]

Reboxetine is a selective noradrenaline reuptake inhibitor (NARI). As noradrenaline plays a relevant role in antinociceptive mechanisms, the hypothesis was investigated in this study whether reboxetine has analgetic efficacy.

Twenty-four healthy volunteers were investigated in a crossover design. Reboxetine (2 x 2 mg) or placebo were given for 5 days with the "crossover" following a one-day washout in between. The primary end-points were the N1 and P2 amplitudes of laser evoked somatosensory potentials (laser SEP) of vertex EEG. In addition, visual analogue scales (VAS, 100 mm) were used.

Reboxetine showed a higher analgesic potency than placebo, with a statistically significant superiority in capsaicinirritated skin--in the objective tests (laser SEP, P < 0.0001 for N1 and P = 0.0002 for P2) as well as in the subjective pain measurements (VAS, P < 0.0003). Besides pain, the subjective feelings of burning and itching were lower with reboxetine than with the placebo.

The hypothesis that a selective noradrenergic substance could be of analgesic efficacy was proven the first time experimentally. Reboxetine reduced the N1 and the P2 components of the laser SEP, which speaks for central and peripheral mechanisms of action.