The effects of idazoxan on reaction times, eye movements and the mood of healthy volunteers and patients with upper respiratory tract illnesses

Abstract

An experiment was carried out to determine whether idazoxan, a drug which increases the turnover of central noradrenaline, removes the malaise (reduced alertness, slower psychomotor performance) associated with upper respiratory tract illness (URTI). Eighty-one volunteers were tested when healthy and 17 returned to the laboratory when they developed URTIs. Those who remained healthy were then recalled as a control group. Volunteers were tested before and after receiving either idazoxan (40mg) or a lactose placebo. Idazoxan removed the URTI-induced slowing in a simple reaction time task and this group performed at a comparable level to the healthy group. No significant stimulant effect of idazoxan was found in the healthy subjects. The results suggest that at least part of the malaise induced by URTIs may reflect reductions in central noradrenaline and that this can be reversed by compounds such as idazoxan.

An investigation of the effects of the common cold on simulated driving performance and detection of collisions: a laboratory study

“…Previous research has shown that the low alertness state associated with a cold can be reversed by a drug that increases the turnover of central norepinephrine. 16 Indeed, ingestion of caffeine, which increases alertness, has been shown to remove the cold-induced performance impairments seen in laboratory tasks. 17 This suggests that a further study examining whether caffeine can remove the effects found here is required.…”

Behavioral Effects of Upper Respiratory Tract Illnesses: A Consideration of Possible Underlying Cognitive Mechanisms

“…Studies of experimentally induced colds have shown that volunteers with colds have impaired psychomotor functioning (poor hand-eye co-ordination, slower response times in reaction time tasks [5,13,14]). Again, these findings have been replicated in studies of naturally occurring colds [15,16,17,18,19,20,21,22,23]. Some studies have used virological assays [20] to ensure that upper respiratory tract infections are being studied.…”

“…Secondly, it could reflect neurotransmitter changes produced by immunological responses to the viral infection. Indeed, research suggests that compounds that increase central noradrenaline (e.g., caffeine [18], idazoxan [21]) remove the drowsiness and psychomotor slowing associated with having a cold. People with upper respiratory illnesses have also been found to be more sensitive to other factors that can change alertness (e.g., noise [15]; alcohol [16]; fatigue [22]).…”

Twenty-five years of research on the behavioural malaise associated with influenza and the common cold

“…The starting point for this line of research was a study which showed that caffeine removed many of the impairments induced by URTIs (Smith et al, 1997). This led to a study examining whether increases in the turnover of central noradrenaline (produced by the drug idazoxan) could remove the impairments seen in those with a cold (Smith et al, 1999b). The results showed that compounds that increase central noradrenaline may remove the reduced alertness and psychomotor slowing associated with URTIs.…”