Definition. - An ester of carbamic acid,

obtained by the reaction of ethyl alcohol upon urea (carbamide) or one of its salts. Reaction:

Description and Properties. - It occurs as colorless, odorless, columnar, or tabular crystals, having a pleasant, cooling, and saline taste, somewhat resembling that of saltpetre. It is soluble in about I part of water, and in like proportion in ether and chloroform, in 0.6 part of alcohol, 0.8 part of liquefied carbolic acid, 3 parts of glycerin, 15 parts of castor oil, and 20 parts of olive oil.

Dose.- 10-45 grains (0.6-3.0 Gm.) [15 grains (1 Gm.), U. S. P.].

Its physiological action resembles others of the alcohol narcotics. The presence of (NH1) groups prevents an overaction as a hypnotic, and in large doses may even destroy its sleep-producing effects, causing stimulation as in ammonia. It is less depressing upon the circulation and respiration than chloral, but more so upon the peripheral ends of the motor nerves. Acting directly upon the cerebrum, it produces a refreshing and dreamless sleep, with no unpleasant after-effects. Nevertheless, it is not so reliable a hypnotic as chloral, and its usefulness as a therapeutic agent is still a debatable question, probably no hypnotic having been introduced concerning the effects of which there is such diversity of opinion. It may be given in capsules or in some pleasant water or syrup, and may also be conveniently administered as an injection by the rectum.