Effects of nefopam on visual tracking.

The effects of 2 doses of nefopam, d-amphetamine, pentazocine, and placebo were studied in healthy male sleep-deprived volunteers to determine whether the drugs improved or impaired coordination and whether they induced subjective effects. A critical tracking task was used to study hand-eye coordination. D-amphetamine, 10 mg orally, significantly improved tracking performance and made subjects feel better able to perform tasks but more anxious. It also made them feel more alert, steady, sociable, and strong. Pentazocine, 45 mg intramuscularly, caused deterioration in tracking performance and was followed by reports of depression, gloominess, dreaminess, nausea, and injection site pain. There was no significant change in tracking performance or subjective effects after both doses of nefopam and placebo.