TRICHLORETHANOL, TRIBROMETHANOL, CHLORAL HYDRATE AND BROMAL HYDRATE

¹ Department of Physiology and Pharmacology, University of Louisville School of Medicine

1. From a consideration of the pharmacodynamic properties of chloral hydrate, bromal hydrate, trichlorethanol, and tribromethanol, it appears unlikely that these alcohols are formed as such from the corresponding aldehyde hydrates in the body. Accordingly, trichlorethanol probably plays no part in the hypnotic action of chloral hydrate.

2. For narcotic potency, tribromethanol = trichlorethanol > chloral hydrate, compared by weight. On a molecular basis, tribromethanol is about twice as active as trichlorethanol in producing narcosis. In depressing respiration, tribromethanol is much more active than trichlorethanol and chloral hydrate. Circulatory depression from tribromethanol and trichlorethanol is about the same, less from chloral hydrate.

3. Bromal hydrate differs completely from the other compounds, lacking soporific properties, actively constricting smooth muscle, and exerting a tonic action on the heart.

4. Trichlorethanol deserves clinical study as a basal anesthetic.