Pyridostigmine, diethyltoluamide, permethrin, and stress: a double-blind, randomized, placebo-controlled trial to assess safety.
Author(s): Roy MJ, Kraus PL, Seegers CA, Young SY, Kamens DR, Law WA, Cherstniakova SA, Chang DN, Cooper JA, Sato PA, Matulich W, Krantz DS, Cantilena LR, Deuster PA
Affiliation(s): Division of Military Internal Medicine, Department of Medicine, Room A3062, Uniformed Services University, 4301 Jones Bridge Rd, Bethesda, MD 20814, USA. firstname.lastname@example.org
Publication date & source: 2006-10, Mayo Clin Proc., 81(10):1303-10.
Publication type: Multicenter Study; Randomized Controlled Trial
OBJECTIVE: To determine whether short-term human exposure to pyridostigmine bromide, diethyltoluamide, and permethrin, at rest or under stress, adversely affects short-term physical or neurocognitive performance. PARTICIPANTS AND METHODS: A multicenter, prospective, double-blind, placebo-controlled crossover trial exposing 64 volunteers to permethrin-impregnated uniforms, diethyltoluamide-containing skin cream, oral pyridostigmine, and corresponding placebos was performed. Each participant had 4 separate sessions, ensuring exposure to all treatments and placebos under both stress and rest conditions in random order. Outcomes Included physical performance (handgrip strength and duration, stair climbing, and pull-ups [males] or push-ups [females]), neurocognitive performance (computerized tests), and self-reported adverse effects. RESULTS: Permethrin was undetectable in the serum of all participants; pyridostigmine levels were higher Immediately after stress (41.6 ng/mL; 95% confidence Interval, 35.1-48.1 ng/mL) than rest (23.0 ng/mL; 95% confidence Interval, 19.2-26.9 ng/mL), whereas diethyltoluamide levels did not significantly differ by stress condition. Heart rate and systolic blood pressure increased significantly with stress compared with rest but did not vary with treatment vs placebo. Physical and neurocognitive outcome measures and self-reported adverse effects did not significantly differ by exposure group. CONCLUSION: Combined, correct use of pyridostigmine, diethyltoluamide, and permethrin is well tolerated and without evidence of short-term physical or neurocognitive impairment.