DOSE-RELATED EFFECTS OF ORAL ACETAMINOPHEN ON COLD-INDUCED PAIN - A DOUBLE-BLIND, RANDOMIZED, PLACEBO-CONTROLLED TRIAL

The cold-presser test is a widely used pain-induction model in humans, This method has been shown to be a sensitive measure for detecting op ioid analgesia. However, nonsteroidal anti-inflammatory drugs have not produced consistent analgesic effects with use of this model, The ana lgesic effect of acetaminophen (INN, paracetamol) on cold presser-indu ced pain has not been reported by other investigators, In this study, a double-blind, randomized, placebo-controlled design was used to eval uate the dose-related effects of oral acetaminophen on cold presser-in duced pain in 18 normal healthy human subjects, We observed dose-relat ed analgesic activity of oral acetaminophen using the cold presser-ind uced pain model in these subjects, There were statistically significan t main effects of both dose and time (pain and bothersomeness ratings decreased with increasing drug dose and increased over time). In pairw ise comparisons only the contrast between the highest dose of acetamin ophen (1000 mg) and placebo reached statistical significance, Results from our study suggest that the cold-presser method may have clinical value in evaluating nonopioid analgesic agents.