THE TOXICITY OF DILAUDID INJECTED INTRAVENOUSLY INTO MICE

¹ From the Department of Physiology and Pharmacology, Duke University School of Medicine, Durham, N. C.

The intravenous toxicity of dilaudid for mice has been determined on three separate occasions, using 99, 57 and 99 mice respectively. The L.D.50 was found in two instances to be 80 and 96 mgm. per kilogram, there being no significant difference between these figures. In the third instance it was 61 mgm. per kilogram, a difference probably to be attributed to a difference in season and in strain. Two similar determinations were made for morphine: the L.D.50 was found to be 318 and 226 mgm. per kilogram, a significant difference and due probably to the same reasons. At the 50 per cent death point dilaudid is 3.7 to 3.8 times as toxic as morphine. In the pair of curves made in the autumn this value is maintained fairly closely throughout all dose ranges, but in the pair of curves made in the summer this ratio increases with decreasing mortality reaching 11.7 at an expected mortality of 0.01 per cent. It is therefore necessary to take the expected mortality into account when comparing the toxicity of two drugs. Similar considerations probably apply to other effects of these drugs.