Speed of action of atropine on sweating

¹ U.S. Army Edgewood Arsenal, Chemical Research and Development Laboratories, Edgewood Arsenal, Maryland

The influence of intravenously injected atropine sulfate on sweating was measured in three men by continuous recording of body weight. Most of the skin surface was kept dry by air movement at 1.5 m/sec. The sequence of events was: completion of injection in 1.1 min; cardiac acceleration in 1.3 min; and inhibition of sweating in 3.5 min. The minimum rate of weight loss occurred at a dose of 0.5 mg; larger doses prolonged the inhibition without intensifying it. Heat storage was equal to an average of 92% of the deficit in evaporative heat loss. Although sweating returned to the initial rate within an hour, the normal increase in sweating at elevated body temperatures was prevented for the next hour. Sweating responds to atropine almost as rapidly as the cardiac rate. The degree of inhibition is independent of the initial rate of sweating.

Submitted on June 24, 1964