2007, Piran, Slovenia

Environmental Ergonomics XII
Igor B. Mekjavic, Stelios N. Kounalakis & Nigel A.S. Taylor (Eds.), © BIOMED, Ljubljana 2007
EFFECT OF ANTI-MOTION SICKNESS DRUGS ON MOTION
SICKNESS-INDUCED PREDISPOSITION TO HYPOTHERMIA
Gerard Nobel 1 , Ola Eiken 2 , Arne Tribukait 2 , Roger Kölegård 2 , Igor B. Mekjavic 3
1 Royal Netherlands Navy, Nethertlands
2 Swedish Defense Research Agency, Karolinska Institute, Berzelius v. 13, SE-17177
Stockholm, Sweden
3 Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Jamova 39,
SI-1000, Ljubljana, Slovania
Contact person: nobel_gerard@hotmail.com
INTRODUCTION
Previous studies have shown that motion sickness (MS) potentiates the cooling rate of the
body core during immersion, both in luke-warm water (28°C) 1 and cold water (15°C) 2 . The
aim of the present study was to investigate whether it is possible to influence this MSinduced
predisposition to hypothermia by administering two commonly used anti-MS drugs,
namely the histamine-receptor blocker dimenhydrinate (Amosyt®) and the muscarinereceptor
blocker scopolamine (Scopoderm®).
METHODS
The study was approved by the Human Ethics Committee at the Karolinska Institute. After
giving their informed consent 9 healthy male subjects participated in 5 experimental
conditions. The subjects’ mean (range) age, weight, and length were 25 (23-27) year, 73 (60-
83) kg and 1.80 (1.68-1.87) m, respectively. After baseline recording and administration of
certain combinations of the two drugs and their respective placebo substances each subject
was immersed in 15°C water for a maximum of 90 minutes or till the core temperature had
dropped 2°C or had reached 35°C. The experimental conditions were:
1. Control: no MS provocation, no medication.
2. Control MS: MS provocation, no medication.
3. Placebo MS: placebo Amosyt® and placebo Scopoderm®, MS provocation .
4. Amo MS: Amosyt® medication, MS provocation.
5. Scop MS: Scopoderm® medication, MS provocation.
MS provocation was induced by the use of a rotating chair in combination with a regimen of
standardized head movements. Throughout the experiments rectal temperature, mean skin
temperature, the difference in temperature between forearm and 3 rd finger of the right hand,
oxygen uptake, heart rate and blood pressure were recorded, but only the results of the rectal
temperature are presented here. At 5-min intervals (after MS provocation) each subject rated
motion sickness, thermal comfort and temperature perception.
RESULTS AND DISCUSSION
Amosyt® and Scopoderm® were similarly efficacious in ameliorating nausea during and
after the MS provocation. During immersion the core cooling rate (∆ rectal temperature) was
28 % greater in the MS control condition than in the Control condition (p