Performance studies with antihistamines.

Abstract

1Effect of four antihistamines, chlorpheniramine (4 mg), clemastine (1 mg), promethazine (10 mg) and terfenadine (60 mg), on visuo-motor coordination and on subjective assessments of performance and well-being were compared with placebo in six healthy females from 0.5-7.0 h after morning ingestion of each drug. The study was double-blind, and the doses used were believed to be equally potent in their antihistaminic activity. 2 There was impaired performance 1.5 h (P< 0.01) after chlorpheniramine, 3.0 h (P< 0.05) and 5.0h (P<0.01) after clemastine, and 3.0h (P<0.01) and 5.0h (P<0.001) after promethazine. It was not possible to establish effects on performance after ingestion of terfenadine. Subjective assessments of performance were not altered. 3 The subjects as a group reported improved alertness (P< 0.05) and improved wakefulness (P< 0.05) 0.5 h and 3.5 h respectively after ingestion of terfenadine, and were less energetic (P <0.05) 7.0 h after ingestion of chlorpheniramine. There were no other consistent changes in assessments of well-being.

Promethazine, scopolamine and cinnarizine: comparative time course of psychological performance effects

“…Promethazine has been shown to significantly impair psychomotor performance in several previous trials. Clarke and Nicholson (1978) demonstrated significant impairments in adaptive tracking 3 and 5 h post-drug, and non-significant impairments 1.5 and 7 h post-drug, following 10 mg oral promethazine. The Clarke and Nicholson (1978) study comprises the only other investigation into the psychomotor performance effects of promethazine for longer than 3 h; their time course data closely matches the present findings (Fig.…”

“…Parenteral promethazine comprises a standard treatment for personnel already vomiting, although the consequent sedation is marked (McMurray 1973;Hordinsky et al 1982). Oral promethazine significantly impairs psychomotor skills such as hand-eye coordination and adaptive tracking (Molson et al 1966;Large et al 1971;Clarke and Nicholson 1978), reduces critical flicker fusion threshold (Turner 1968;Hedges et al 1971), and leads to lowered feelings of alertness (Hedges et al 1971;Large et al 1971). The effects of oral promethazine upon information processing and cognitive skills to not seem to have been investigated, although parenteral promethazine impairs information processing (Hordinsky et al 1982).…”

“…Parrott (1986) reported significant impairments 1-2 h after 1.2 mg oral scopolamine, while performance returned near to baseline 5 6 h post-drug. With oral promethazine, Clarke and Nicholson (1978) demonstrated maximal impairments 5 h after drug administration, while performance remained below baseline 7 h post-drug. Hedges et al (1971) demonstrated maximal decrements 6 h post-drug (later periods were not assessed).…”

Histamine H1-receptor blockade in humans affects psychomotor performance but not memory

“…Two studies have shown that single oral doses of 4 mg chlorpheniramine produced significant performance impairment, which was most pronounced shortly after t max (Kamei et al, 2003;Witek et al, 1995). Yet, in a third study performance was significantly impaired only at 1.5 h after drug administration (Clarke and Nicholson, 1978). On the basis of these results it was decided to measure the effects of dexchlorpheniramine at both times reported for peak impairment that is between 1.5 and 2.5 h and between 3.5 and 4.5 h after administration.…”

Lack of interaction between two antihistamines, mizolastine and cetirizine, and ethanol in psychomotor and driving performance in healthy subjects

“…So far, however, combinations of ethanol with the newer "non-sedative" antihistamines (terfenadine, astemizole, cetirizine, loratidine or ebastine) have not shown potentiation [12][13][14][15][16][17][18][19]. Yet it is important to evaluate the interaction of each new antihistamines with ethanol, since there is the possibility that this new drug, non-sedative by itself, will somehow potentiate with alcohol.…”