A ketone C9H16CO obtained from Cinnamomum Camphora, purified by sublimation.

Properties : Camphor occurs as white translucent masses of a tough consistence and a crystalline structure, readily pulverizable in the presence of a little alcohol, ether or chloroform; It has a characteristic odor and a pungent taste. It is very slightly soluble in water but freely soluble in alcohol, ether, chloroform and in fixed and volatile oils.

Action and Uses: Camphor stimulates the central nervous system, especially the medullary centers, and the circulation; locally it is mildly irritant and antiseptic. In toxic doses it produces delirium followed by unconsciousness with epileptiform convulsions. It has been used as a nerve depressant in epilepsy and convulsions, but owing to its stimulating action this use seems irrational.

Camphor tends to increase the blood-pressure. The effects on animals are complex and rather inconstant, but clinically large doses of camphor improve the pulse in impending cardiac collapse, probably by cardiac. stimulation. For this reason it is used as a circulatory and respiratory stimulant in cases of collapse, syncope, cardiac failure, etc. It should be administered hypodermically, 0.5 c.c. of a 10 per cent, sterile solution in olive oil being injected every fifteen minutes for four doses if needed.

The antiseptic action of camphor is utilized in gargles and mouth washes. It is also given in dyspepsia as a carminative, and is used in the first stage of colds and other infections of the respiratory tract. It acts internally as a diaphoretic.

Locally camphor causes a loss of tone of the peripheral blood-vessels, and thus produces marked redness of the skin. It has also a local anesthetic action. It is employed for its mild rubefacient and counterirritant effects, as an ingredient of liniments.

Dosage: 0.10 gm. or about 2 grains.

The average dose of camphor is commonly given as 2 grains, but when a prompt cardiac or central action is demanded, much larger doses may be required. It may be given in an oily or alcoholic solution or in pills, capsules or cachets.