Croton-chloral (Unofficial). - Origin. - Prepared by passing dry chlorine gas into acetic aldehyde, resulting in the formation of butyl-chloral, which is separated by fractional distillation, and water added.

Description and Properties - Butyl-chloral occurs as a heavy, colorless oil, having an odor resembling that of cnloral. The hydrate (croton-chloral hydrate) used in medicine is in the form of white scales, of a silky luster, nauseous taste, and a peculiar fruit-like odor. It is freely soluble in alcohol, ether, glycerin, and hot water, but not easily soluble in cold water. Its solutions are unstable, and are decomposed if kept on hand even for a short time.

Dose. - 3-20 grains (o. 18 - 1.2 Gm.).

Incompatibles and Synergists are the same as for chloral.

Its physiological action and therapeutics are quite similar to those of chloral. It was at one time thought that its analgesic properties were more pronounced than chloral and was highly recommended in facial neuralgia. For the severe cases it is worthless, and for the milder cases other analgesics are far better. It has now little practical use.

Chloral-ammonium. - Obtained by passing a rapid current of dry ammonia through a solution of anhydrous chloral and chloroform as long as it is absorbed. Its chemical name is trichloramidethylic alcohol. It occurs as small, white acicular crystals, and is soluble in alcohol and slightly soluble in water, although the aqueous solution is unstable.

Dose. - 15-30 grains (1.0-2.0 Gm.).

It has no advantages over chloral.

Chloralose. - Prepared by heating equal quantities of anhydrous chloral and dry glucose ; hence the name, chloral-ose.

Description and Properties. - It occurs in the form of fine needles, completely volatilizing without decomposition. It has an acrid, nauseous taste, and is soluble in hot water and in alcohol.

Dose. - 2-10 grains (0.12-0.6 Gm.).

Chloralose has been found to be more depressing than chloral.

1 Deut. med. Woch., 1889, No. 49.

Hypnal. - A compound of chloral and antipyrine, known as monochlorantipyrine. A similar preparation containing more chloral is called dichloralaniipyrine.

Description and Properties. - It occurs in the form of transparent, rhombic crystals, odorless and tasteless, soluble in from 5 to 6 parts of water. Dose. - 5-20 grains (0.35-1.3 Gm.).

The addition of the antipyrine to increase analgesia, while hypothetically good, has not proven of service.

Ural - Chloral-urethane - Uralium. - A compound of urethane and chloral hydrate.

Description and Properties. - A crystalline body, soluble in alcohol and ether, insoluble in cold water, and decomposed by boiling water.

Chloretone - acetone chloroform - is the trade name of an old chemical compound, trichlopseudo butylalcohol.

Description and Properties. - It is a white, crystalline substance, sparingly soluble in cold water, but freely soluble in hot water, ether, alcohol, and chloroform. It has a camphoraceous odor and a not unpleasant taste.

Dose. - 5-10 grains (0.30-0.60 Gm.) or even double this dosage. Best administered in powders or in alcoholic menstruum.

This is undoubtedly a useful hypnotic with an action very similar to that of chloral, but if the recent studies of Impens are to be trusted, it is 2 1/2 times as poisonous as chloral. Chloretone is an excellent antiseptic as well as a hypnotic and has been widely used as a dusting-powder for wounds. It has also been employed in the eye and is a marked local anesthetic. Poisonous local effects are reported, however -intense local edema, etc.

Isopral is a closely related compound (trichloriso propyl alcohol).

Hypnone. - As a hypnotic a much weaker substance than chloral, although it has found some advocates as a remedy for the insomnia of alcoholism. Toxic doses paralyze the heart and respiration. It should be given in capsules.