Midazolam causes less sedation in volunteers with red hair.
OBJECTIVE
We studied sedation, cognition, and mood during midazolam infusion in volunteers with red and non-red (blond or brown) hair, to test the hypothesis that patients with red hair may require more drugs to attain desired levels of sedation.


METHODS
Twenty red and 19 non-red hair subjects were studied in a randomized, placebo-controlled cross-over design. Subjects were studied during placebo and midazolam at 30 ng.mL(-1) target effect site concentration. Sedation was assessed using the observer's assessment of alertness/sedation (OAA/S) scale, the drowsiness visual analogue scale (VAS), and the bispectral index; cognition was assessed using the Repeatable Battery for Assessment of Neuropsychological Status; and mood was assessed using the bipolar form of the Profile of Mood States (POMS).


RESULTS
Red hair volunteers showed significantly higher OAA/S (P < 0.01) and lower drowsiness VAS (P < 0.05) scores compared to non-red hair subjects during midazolam infusion. Visuospatial score was significantly higher in subjects with red compared to non-red hair during placebo and midazolam trials. Delayed memory score was significantly higher during midazolam infusion in subjects with red compared to non-red hair. There were no group differences in POMS during either trials.


CONCLUSIONS
Midazolam appears to cause significantly less sedation and cognitive impairment in red haired subjects.
Chua
Marlene V
MV
Department of Anesthesiology and the Outcomes Research Institute, University of Louisville School of Medicine, Louisville, Kentucky 40292, USA.
Tsueda
Kentaro
K
Doufas
Anthony G
AG
D000328:Adult; D000339:Affect / Q000187:drug effects; D003071:Cognition / Q000187:drug effects; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004569:Electroencephalography / Q000187:drug effects; D005260:Female; D006200:Hair Color / Q000502:physiology*; D006801:Humans; D006993:Hypnotics and Sedatives / Q000494:pharmacology*; D008297:Male; D008874:Midazolam / Q000494:pharmacology*; D009483:Neuropsychological Tests; D012894:Sleep Stages / Q000187:drug effects
D006993:Hypnotics and Sedatives; D008874:Midazolam