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Published on: October 16, 2013
Midazolam causes less sedation in volunteers with red hair
Marlene V Chua1, Kentaro Tsueda, Anthony G Doufas
1Department of Anesthesiology and the Outcomes Research Institute, University of Louisville School of Medicine, Louisville, Kentucky 40292, USA.
Purpose:
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.
Conclusion:
Midazolam appears to cause significantly less sedation and cognitive impairment in red haired subjects.
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