Abstract
Effects of aspirin (325 and 650 mg) and paracetamol (500 and 1000 mg), and of the centrally acting analgesics meptazinol (100 and 200 mg) and pentazocine (25 and 50 mg) on visuo-motor coordination and dynamic visual acuity, together with critical flicker fusion, digit symbol substitution, complex reaction time and subjective assessments of mood, were studied from 0.75–2.0 h after ingestion by seven healthy female adults. The study was double-blind and placebo controlled, and triprolidine (10 mg) was used as the active control. No effects of meptazinol and paracetamol on performance were observed. Pentazocine (25 mg) impaired performance on digit symbol substitution (ppp<0.05). Impaired performance with pentazocine may involve opioid receptor activity, while the apparent alerting effect of meptazinol may relate to its cholinergic activity. The possible effect of aspirin on reaction time needs to be confirmed.