If there is any tendency to become complacent about the adequacy of knowledge in a given area, a review of the subject usually serves to dispel this attitude. Although there exists a formidable body of knowledge on the pharmacology of the hypnotics and sedatives, that which remains unknown is even more formidable. Many of the experiments which have yielded information on the pharmacodynamics and disposition of these drugs in laboratory animals do not have their counterparts in human studies. In such instances, only a logical guess can be made in an effort to bridge this gap. The known effects of the barbiturates, bromides, paraldehyde, chloral hydrate, and newer hypnotics and sedatives in man are presented and an attempt is made to compare these with findings in other species. Where data of a critical nature with respect to the human pharmacology of these drugs are lacking, the fundamental features of their actions on other animals are presented.
In addition to the more classic aspects of their pharmacodynamics, the more significant alterations in behavior produced by these agents are summarized. Studies dealing with their pharmacology in both the normal and pathologic states and in therapeutic and toxic dosages are outlined. Finally, the disposition of these compounds in the body is considered, inasmuch as this aspect of their pharmacology may have important bearing on the responses elicited by them in the organism.