ENVIRONMENTAL TEMPERATURE AND DRUG ACTION IN MICE

¹ From the Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, and the Laboratories for Experimental Medicine, University of Cincinnati, Cincinnati

1. Of 11 drugs studied in mice at various temperatures, diamino-diphenyl sulfone given by mouth is shown to be approximately 10 times as toxic at 40°C. as at 25°C.

2. Insulin injected by vein is more than 80 times as potent at 40°C. as at 20°C. The onset of convulsions occurs sooner at high temperatures than at low ones.

3. Harmine hydrochloride administered intravenously is also increasingly toxic, although to a less degree, with the rise of temperature. It is about twice as toxic at 40°C. as at 20°C.

4. There is a suggestion that the toxicity of sulfapyridine sodium, sulfathiazole sodium, strychnine sulfate, picrotoxin, tutin, aconitine hydrobromide, and scopolamine hydrobromide, increases with the elevation of temperature— particularly at 40°C. as compared with lower temperatures. The lethal dose of sulfanilamide is least influenced by temperature.

5. Mice appear more susceptible at 40°C. to picrotoxin and tutin in developing convulsions than at 20-25°C. The speed of action is also accelerated at higher temperature levels.