Camphora, B.P. Camphor.
C10H16O = 152.128.
Camphor, C10H16O, is a ketone or a keto-tetrahydro-cymene, obtained from the camphor tree, Cinnamomum Camphora, Nees and Eberm. (N.O. Laurineae), a tree growing abundantly in Formosa, Japan, and the Chinese continent. It is also official in the U.S.P. The wood of the tree in small pieces is subjected to a rough process of distillation with water vapour; crude camphor containing a varying quantity of yellowish oil (camphor oil) is thus obtained, and further purified by resublimation. According to the manner of condensation, it is collected in wide rings known as "bells," or pulverulent masses termed "flowers of camphor." The latter are often compressed into rectangular tablets. Camphor is also produced synthetically by the oxidation of camphene or isoborneol. Camphor occurs as a colourless, transparent, crystalline solid. It has a powerful penetrating odour, and pungent, somewhat bitter, taste, followed by a slight sensation of cold. It burns readily, with a bright smoky flame, volatilises at ordinary temperatures and sublimes without residue when heated. Specific gravity, 0.986 to 0.996 (about 0.990 at 25°). Melting-point, 175° to 179°. It forms a liquid when triturated with chloral hydrate, phenol, menthol, or thymol. Synthetic camphor differs from the natural product in being optically inactive instead of dextrorotatory.
Soluble in water (1 in 700), alcohol (1 in 1.25), olive oil (1 in 4), chloroform (4 in 1), ether (12 in 7), oil of turpentine (1 in 1.5), or glacial acetic acid (2 in 1).
Action and Uses.—When applied externally, camphor dilates the vessels of the skin, and is used as a rubefacient and mild counterirritant. Internally, camphor has much the same action as the volatile oils, and is prescribed as a carminative in flatulence and as an antiseptic for the alimentary canal. It mildly excites the circulation, dilating the superficial vessels and slightly increasing the cardiac output. It also directly excites the cerebrum. It is a popular remedy, either taken by the mouth or used as a snuff, for the relief of colds. For internal use, camphor is administered in the form of a pill, massed with a little soap and glycerin of tragacanth, or sometimes combined with extract of henbane. Camphor water contains about 3 centigrams in 30 mils (½ grain per fluid ounce). Other preparations of camphor for internal use are the spirit (1 in 10 of alcohol), suitable for admixture with sal volatile or ammoniated tincture of quinine in the form of drops, and the essence of camphor (Rubini's Essence, a saturated alcoholic solution) given on sugar or in milk. Paregoric elixir contains camphor in association with opium, anise, and benzoic acid, and is especially useful in chronic bronchitis. Camphor is given hypodermically—1 to 2 decigrams (2 to 3 grains)—dissolved in sterilised olive oil, as a restorative in collapse, especially in pneumonia and other acute fevers. Any value it may have in these conditions must be regarded as due to the stimulant action on the cerebral cortex. It is a common ingredient of stimulating and anodyne liniments. Camphorated oil contains 1 of camphor dissolved in 4 of olive oil; ammoniated camphor liniment (1 in 8) contains strong solution of ammonia, oil of lavender, and alcohol. Camphorated chalk is a popular dentifrice. Stimulating and emollient ointments of camphor for use against chilblains and cracked skin contain about 1 part in 6 parts, with wax, almond oil, and sometimes a small percentage of thymol. The liquid obtained by mixing equal weights of camphor and chloral is used as an anodyne pigment, sometimes with the addition of cocaine. In medicated soaps, camphor is combined with borax, or with sulphur and balsam of Peru. In cases of poisoning by camphor, an emetic should be administered, stimulants, such as digitalis and strychnine, used freely by injection, and warmth applied to the extremities.
Dose.—1 to 3 decigrams (2 to 5 grains).
- Aqua Camphorae, B.P.—CAMPHOR WATER.
- Camphor, 0.1; alcohol, a sufficient quantity; distilled water, sufficient to produce 100. Used chiefly for flavouring purposes, but has a mild carminative, diaphoretic, and expectorant action. Dose.—30 to 60 mils (1 to 2 fluid ounces).
- Aqua Camphorae, U.S.P.—CAMPHOR WATER, U.S.P.
- Camphor, 0.8; alcohol, 0.8; purified talc, 1.5; distilled water, to 100. Average dose.—8 mils (2 fluid drachms).
- Aqua Camphorae Concentrata, B.P.C.—CONCENTRATED CAMPHOR WATER.
- One part of this solution corresponds to 40 parts of camphor water.
- Ceratum Camphorae, U.S.P.—CAMPHOR CERATE.
- Camphor liniment, by weight, 10, white wax, 35; white petrolatum, 15 benzoinated lard, 40.
- Chloroformum Camphoratum, B.P.C.—CAMPHORATED CHLOROFORM. Syn.—Chloroform of Camphor.
- Camphor, 2; chloroform, 1. A common remedy for toothache, applied on cotton wool to the cavity or rubbed along the gums with the finger. For the latter purpose it is sometimes mixed with tincture of capsicum or tincture of pyrethrum.
- Creta cum Camphora, B.P.C.—CAMPHORATED CHALK. 1 in 10.
- A refreshing, cleansing, and entirely harmless dentifrice. It should be stored in a cool place away from direct sunlight, in order, as far as possible, to avoid loss of camphor by evaporation, or by sublimation of the camphor on to the cool side of the bottle.
- Essentia Camphorae, B.P.C.—ESSENCE OF CAMPHOR. Syn.—Spiritus Camphorae Fortior; Rubini's Essence of Camphor, 1 in 2 ½ .
- A common remedy for catarrhal colds. It is taken on sugar, the dose being repeated hourly. Dose.—1 to 3 decimils (0.1 to 0.3 milliliters) (2 to 5 minims).
- Linimentum Camphorae, B.P.—LINIMENT OF CAMPHOR. Syn.—Camphorated Oil.
- Camphor, in flowers, recently sifted, 20; olive oil, 80. Liniment of camphor is a stimulant and rubefacient application, and is used as a counter-irritant to rub the chest in the bronchitis of children, or for rubbing on painful joints, Liniment of camphor is an excellent antidote in carbolic acid poisoning.
- Linimentum Camphorae, U.S.P.—CAMPHOR LINIMENT.
- Camphor in coarse powder, 20; cotton seed oil, by weight, 80.
- Linimentum Camphorae Ammoniatum, B.P.—AMMONIATED LINIMENT OF CAMPHOR. Syn.—Linimentum Camphorae Compositum; Compound Liniment of Camphor.
- Camphor, 12.5; oil of lavender, 0.625; strong solution of ammonia, 25 alcohol, sufficient to produce 100. A powerful counter-irritant for use in chest complaints, chronic rheumatism, neuralgia, etc. The ammonia is the most active constituent.
- Spiritus Camphorae, B.P.—SPIRIT OF CAMPHOR.
- Camphor, 10; alcohol, sufficient to produce 100. Given on sugar as a diaphoretic and expectorant for colds. Dose.—3 to 12 decimils (0.3 to 1.2 milliliters) (5 to 20 minims).
- Spiritus Camphorae, U.S.P.—Similar to B.P., but made with alcohol (95 per cent.).
- Spiritus Camphorae Compositus, B.P.C.—COMPOUND SPIRIT OF CAMPHOR.
- Each fluid drachm contains ⅛ grain of camphor, ¼ grain of benzoic acid, ⅛ minim of oil of anise, with glycerin, burnt sugar, to colour, and alcohol (60 per cent.). It is added to children's cough mixtures as a mild expectorant. Dose.—2 to 4 mils (½ to 1 fluid drachm).
- Unguentum Camphorae, B.P.C.—CAMPHOR OINTMENT. 1 in 10.
- A mild counter-irritant and analgesic. It relieves superficial pain and irritation, and is used for chilblains and pruritus.
- Unguentum Camphorae Durum, B.P.C.—HARD CAMPHOR OINTMENT. Syn.—Camphor Ice. 1 in 10.
- Used as an emollient for the skin. It promotes the healing of cracks in the skin arising from cold and exposure.
- [For preparations of camphor containing opium see under Opium.]