TOXICITY, ANTIPYRETIC AND ANALGESIC STUDIES ON 39 COMPOUNDS INCLUDING ASPIRIN, PHENACETIN AND 27 DERIVATIVES OF CARBAZOLE AND TETRAHYDROCARBAZOLE

¹ Department of Physiology, The University of Chicago

1. Studies on the acute oral toxicity, antipyretic activity, analgesic activity, and the ability to lower the body temperature of normal rats were made on a total of thirteen carbazoles, fourteen tetrahydrocarbazoles, aspirin, phenacetin and ten other compounds.

2. Of the standards used phenacetin was less toxic, had greater antipyretic and analgesic activity, had a higher antipyretic index and had a greater temperature-lowering effect on normal rats than aspirin.

3. Tetrahydrocarbazole itself was more toxic than carbazole and the various derivatives of the former were generally more toxic than the corresponding derivatives of the latter.

4. Of the 39 compounds studied, 19 were less toxic, 23 had greater antipyretic activity, 22 had greater analgetic activity and 25 had a higher antipyretic index than aspirin; 7 of the compounds were superior to aspirin in all respects.

5. Fifteen of the compounds were less toxic, 16 had greater antipyretic activity, 17 had greater analgesic activity and 6 had a higher antipyretic index than phenacetin.

6. At a dose level of 200 mgm./kgm. fifteen of the compounds caused average depressions in the body temperature of normal (non-fevered) rats of as much as 3.1 to 8.4°F. below that of the room control rats.