Origin. - A monatomic phenol occurring in coal-tar, but usually prepared artificially from naphthalene.

Description and Properties. - Colorless or pale buff-colored, shining, crystalline lamince, or a white or yellowish-white crystalline powder, having a faint, phenol-like odor, and a sharp, pungent, but not persistent, taste. Permanent in the air. Soluble in about 95 parts of water, in 0.6 part of alcohol at 250 C. (770 F.), in about 75 parts of boiling water, and very soluble in boiling alcohol, ether, chloroform, and solutions of caustic alkalies. It should be kept in dark amber-colored, well-stoppered bottles.

Dose. - 2-10 grains (0.12-0.6 Gm.) [4 grains (0.250 Gm.), U. S. P.].

Antagonists and Incompatibles. - Physiological antagonists of naphthalene are the same as for other members of this group. Betanaphthol is incompatible with subacetate of lead.

Synergists. - Carbolic acid and its derivatives.

Physiological Action. - Naphthalene is antiseptic, antifer-mentative, disinfectant, and deodorant. Its action is quite similar to phenol. It is insoluble in the gastric juices, but to some extent soluble in the intestines, where it acts as an antiseptic by local contact, deodorizing the stools and often imparting to them its own odor. It is absorbed to some extent, and is eliminated by the lungs and kidneys, but escapes principally in the feces. It has been known to irritate the kidneys. It is broken up into naphthol or dioxynaphthalene, and acts as a local antiseptic and disinfectant at points of elimination, but does not occasion any local irritation unless quite large doses have been taken: 15 grains (1.0 Gm.) daily have occasioned frequent micturition, with burning pain, vesical tenesmus, and redness of the urethral orifice. Purdy states that in certain cases of genito-urinary disease he has known a dose of 5 grains (0.32 Gm.) to cause severe suffering along the whole urinary tract. It is a stimulant expectorant. Its use is thought to bring about a cloudiness of the crystalline lens.

Betanaphthol is quickly absorbed when applied locally. It produces considerable irritation when used in solution, but has no irritating effect when applied in the form of ointment. Toxic effects may result from its absorption by the skin, their character resembling the action of carbolic acid.

Therapeutics. - Externally and Locally. - Naphthalene is recommended in the treatment of scabies and other parasitic skin diseases.

Internally. - It is used in typhoid fever and in the gastro-intestinal and genito-urinary disorders for which salol and carbolic acid are administered, such as chronic diarrhea and dysentery, acute or chronic cystitis, etc.

The internal uses of Betanaphthol are the same as those of naphthalene, while externally it may be employed, like carbolic acid or creasote, as a general antiseptic in cutaneous disorders, whether organic or parasitic.

Allied Compounds

Alumnol. - An almost colorless, non-hygroscopic powder; readily soluble in cold water or glycerin, less soluble in alcohol, and insoluble in ether. It is employed as a local remedy in solutions varying in strength from I to 50 per cent. Used externally. It is aluminium naphtholdisulphonate.

Asaprol. - A colorless, neutral crystalline powder, soluble in 11/2 parts of water and 3 parts of alcohol. - Dose, 15-60 grains (1.0-4.0 Gm.). Beta-naphthol sodium sulphonate. It is prescribed as an antipyretic.

Benzonaphthol. - Obtained by the action of benzoic-chloride on beta-naphthol in a sand-bath. It is an odorless, tasteless, white, crystalline powder, or occurs in the form of long needles. Insoluble in cold water. Dose, 4-8 grains (0.18-0.5 Gm.).

Betol (Naphtosalol - Salinaphthol). - A substance analogous to salol, and prepared in the same manner, except that sodium-naphthol is used instead of sodium-phenol. It occurs as a colorless, odorless, tasteless, lustrous crystalline powder. Insoluble in water or glycerin, and with difficulty soluble in cold alcohol. Dose, 2-5 grains (0.12-0.3 Gm.).

Camphorated Naphthol. - Obtained by mixing 1 part of beta-naphthol with 2 parts of camphor. It is a brownish, transparent, syrupy liquid.

Hydronaphthol. - A derivative of beta-naphthol, obtained by the action of reducing agents. It occurs in scale-like crystals, of a silvery-white or grayish hue, of slightly aromatic odor and taste. Soluble in 1100 parts of water, and freely soluble in alcohol, ether, glycerin, benzene, chloroform, and fixed oils. Dose, 2-3 grains (0.12-0.18 Gm.).

Asaprol, betol, and hydronaphthol are best given in capsules, although betol, which is tasteless and insoluble in water, may be administered in the form of powders.

Alumnol. - An efficient remedy in many acute and chronic inflammatory diseases of the skin, and in gonorrhea, chancres, syphilitic ulcers, balanitis, etc. A 1 per cent. solution may be injected in gonorrhea, while stronger solutions (10-50 per cent.), or alumnol plaster, are recommended in chronic diseases of the skin.

Asaprol. - Given for the same purposes as salicylic acid and the salicylates, although it is not so uniformly successful in acute articular rheumatism, while having the advantage of causing less heart-depression.

Betol. - Used chiefly in the bowel complaints of children. It may be administered either by the mouth or through the rectum, associated with bismuth or antacids. It has been used also in acute articular rheumatism and bladder affections.

Camphorated naphthol is considered by some practitioners to be superior to all other remedies to prevent suppuration in acute tonsillitis.

Fernet has employed it successfully in tuberculous ulcerations of the tongue, while Reboul, of Marseilles, and others have adopted it with good effect hypodermically in tuberculous adenitis and tuberculosis of the testis. It has also been used in tuberculosis of the bladder, joints, etc.

Ruault claims it to be an efficient local application to the turbinated bones in ozena.

Hydronaphthol. - Considered by many physicians to be superior to carbolic acid, since it is without disagreeable odor and can be used without exciting irritation or danger of toxic impression.

Dockrell employs it in the form of a plaster for destroying the trichophyton fungus of tinea tonsurans, and believes it to be superior to mercuric chloride as a germicide.

It has been used as a preventive of dental caries, and in the treatment of gingivitis, pyorrhea alveolaris, diphtheria, etc.

Internally it has been recommeuded in dysentery, diarrhea, pulmonary tuberculosis, and typhoid fever.

Contraindications. - These preparations should not be given internally when the functional activity of the kidneys is defective.

Administration. - Naphthalene is best given internally in the form of pills or in capsules. When it is necessary to use it topically, the offensive odor of the drug may be disguised, it is said, by triturating it with a small quantity of the oil of bergamot. Beta-naphthol should be given in capsules, in the dose recommended, three times a day or oftener if necessary.