THE TRANQUILIZING AND RESPIRATORY DEPRESSANT EFFECTS OF TRIBROM-ETHANOL (AVERTIN), AMYLENE HYDRATE, ISOAMYLETHYLBARBITURIC ACID (AMYTAL) AND ETHYL (1-METHYL-BUTYL) BARBITURATE (PENTOBARBITAL) ALONE AND IN COMBINATION WITH MORPHINE ON THE RAT

¹ From the Department of Pharmacology of the School of Medicine of Western Reserve University, Cleveland, Ohio

1. A comparison of the complete tranquilizing doses and their side effects is furnished in table 1.

2. The tranquilizing and respiratory depressive effects of avertin fluid are almost intermediate between those of the avertin and the amylene hydrate contained in the fluid, i.e., the amylene

[See table in the PDF file]

hydrate apparently reduces the effectiveness of the avertin crystals but to a smaller degree than with large to fatal dosages of the "fluid."

3. The combination of the sedatives with morphine significantly alters the reactions usually observed with morphine alone. These effects are as shown in table 2. This tabulation shows that a mutual potentiation is demonstrable between morphine and either of the three preparations (with the exception of small doses of either of the barbitals) for both tranquilization and respiratory depression, the degree being fairly proportionate for both functions. The order from greatest to least for tranquilization is pentobarbital, avertin crystals, amytal, and for respiratory depression avertin, pentobarbital. Amytal produces a simple summation with morphine on the respiratory minute volume. However, the depressant effects of amytal alone were such that the depression produced by combinations of morphine and amytal was equivalent to that of any of the other combinations tested.