- Definition. - It should contain not less than 99 per cent. of pure zinc valerate (C4H9COO3)ZN + 2H1O.

Origin. - Obtained by evaporating hot solutions of zinc sulphate and sodium valerianate, the zinc valerianate crystallizing out.

Description and Properties. - White, pearly scales, having the odor of valerianic acid and a sweetish, astringent, and metallic taste. On exposure to air it slowly loses valerianic acid. Soluble in about 100 parts of water and in 40 parts of acohol. It should be kept in small, well-stoppered bottles.

Dose. - 1/2-3 grains (0.03-0.2 Gm.) [2 grains (1.25 Gm.), U. S. P.].

Physiological Action. - Externally and Locally. - The only member of this group having any special local action is camphor. This drug has an anesthetic effect upon the unbroken skin, but in a concentrated state is very irritating to mucous membranes, and may even produce inflammation and sloughing. Camphor is also a powerful parasiticide.

Digestive System. - In medicinal doses antispasmodics stimulate the digestion and augment the secretions from the gastro-intestinal tract. They also stimulate peristalsis, and are active carminatives and calmatives to the digestive tract. Asafetida is the most laxative of all.

Large doses of any antispasmodic cause nausea, vomiting, and purging, camphor being the most irritant, and in toxic doses acting as an irritant poison.

Circulatory System. - In medicinal doses the antispasmodics increase the force of the heart and elevate arterial tension.

Nervous System. - It is probably upon the nervous system that these drugs exert their most potent action. They are all stimulants to the cerebrum.

The antispasmodics, it will be seen, appear to exert a calmative influence upon certain nerve-centers, allaying nervous excitement and muscular spasm. They produce a gentle, exhilarating effect upon the brain, and diffuse a feeling of warmth in the system. It is claimed that they also possess mildly aphrodisiac properties. Excessive doses, on the other hand, may occasion delirium, even merging in maniacal excitement, this being particularly true of camphor, toxic doses of which drug, in the monobromated form, cause muscular weakness, passing into paralysis, followed by stupor and collapse. Valerian may occasion formication of the hands and feet and a condition of mental depression.

Respiratory System. - The antispasmodics are all respiratory stimulants and stimulant expectorants. Large doses of monobromated camphor depress respiration.

Absorption and Elimination. - These drugs are readily absorbed from the stomach or rectum, and are eliminated by the intestinal tract, kidneys, lungs, skin, and mucous membranes generally, stimulating the glands in these structures, and, in the case of asafetida and valerian, imparting the characteristic odor of these drugs to the excretions.

Temperature. - Unaffected except by monobromated camphor, which in large doses acts as a depressant.

Uterus. - The menstrual flow and sexual appetite are increased at first; continued dosage, however, has a depressing effect upon the generative functions, camphor perhaps being the most active in large doses.

Asafetida exerts the greatest influence on menstruation, while camphor has the most marked effect upon the general circulation.

It is said that the sexual passion of cats is extraordinarily excited by valerian, probably because of its odor.

Untoward Action. - Camphor may occasion mental confusion, headache, vertigo, dryness of the mouth and thirst, flushing of the face, clammy perspiration, disturbances of digestion, and strangury. Musk produces similar untoward manifestations, with a sense of pressure in the eye-sockets and marked sexual excitement. The symptoms caused by valerian are very much the same, although, as in the untoward action of asafetida, there is more disturbance of the gastro-intestinal tract, such as nausea, borborygmi, diarrhea, and colicky pains. Barbier noted visual hallucinations in a person treated with valerian.

Poisoning. - The symptoms of poisoning resemble the untoward action, save that the effects may be more marked, with greater irritation of the intestinal tract and more pronounced cerebral disturbance.

Treatment of Poisoning. - Coffee and the arterial sedatives antagonize the action of camphor. The patient should be treated symptomatically; emetics or the stomach-pump should be employed, and measures taken to favor elimination. Excessive nervous manifestations may be controlled by opium or the bromides.

Therapeutics. - Externally and Locally. - The only member of the present group used locally is camphor, its anesthetic and antipruritic properties rendering it of great value in the treatment of diseases of the skin. "Anderson's powder," composed of pulverized camphor, starch, and zinc oxide, is a very soothing and efficient dusting-powder in erythema, erythematous eczema, and urticaria. "Camphor-ice" and ointments of camphor, alone or combined with salicylic acid, are used for "chapped hands," ulcers, etc.

Various inhalants and powders containing camphor have been successfully employed in the treatment of ozena, acute coryza, and laryngitis. Suppositories of camphor afford great relief in cases of chordee, while the camphor liniment is a household remedy for sprains, bruises, chilblains, etc.

Camphor chloral makes an efficient local application in neuralgia, and the campho-phenique is an excellent antiseptic, when mixed with oil being an efficient dressing for wounds.

Internally. - The disagreeable odor and taste of many of the antispasmodics - notably asafetida, valerian, and musk - greatly limit their use. Asafetida is an exceedingly valuable stomachic tonic, and singularly beneficial in the atonic dyspepsia and constipation of nervous and anemic women. It stimulates the appetite and digestion, acts as a laxative, and allays much of the nervousness and depression from which these patients so frequently suffer.

Asafetida is a peculiarly potent remedy in relieving paroxysms of hysteria and there is probably no more effective agent for the alleviation of flatulent colic of infants and various infantile convulsions. It is here given in enemata.

Chronic bronchitis and bronchorrhea, especially when attended with spasmodic dyspnea, are very favorably influenced by this remedy. Its antispasmodic action renders asafetida of considerable value in whooping-cough and the sympathetic cough of mothers. The drug has been highly recommended in chorea occurring in young girls about the age of puberty, who are weak, anemic, and suffering from menstrual irregularities. The emulsion of asafetida, used as an enema, often affords prompt and complete relief in the tympanitis of typhoid fever.

Camphor is a remarkably efficient anodyne, antispasmodic, and carminative in flatulent colic, diarrhea of infants, and the diarrhea of the aged produced by relaxation of the bowels. For many years camphor has been considered a valuable remedy in the diarrhea ushering in an attack of Asiatic cholera.

The various spasmodic and hysteric disorders for which asafetida is recommended are also greatly benefited by camphor. It is, moreover, a serviceable stimulant expectorant and a potent remedy, especially monobromated camphor, to allay sexual excitement and for the relief of chordee. It has likewise proved efficacious in spermatorrhea.

Dysmenorrhea and the after-pains of labor are greatly relieved by camphor, either alone or combined, with morphine. The drug has been used extensively as a cardiac stimulant and to allay the delirium and restlessness of typhoid, typhus, and exanthematous fevers.

Camphoric acid is an efficient remedy in checking the night-sweats of phthisis and excessive perspiration in acute rheumatism. It is recommended by Wood in eneuresis and spermatorrhea. While not so efficient as camphor or monobromated camphor in spasmodic and hysteric disorders, it has proved of some benefit in these conditions.

Camphoric acid in from 1 to 2 per cent. solution is useful in the treatment of acute pharyngitis and acute coryza, being employed in the form of a gargle or spray.

Camphoric acid has been used internally to acidify ammoniacal urine in cystitis.

Valerian has been employed for the same class of disorders as those treated with asafetida, but seems to be superior to the latter in mitigating the hysteric manifestations and vasomotor disturbances occurring at the menopause.

The hypochondriasis of feeble and morbidly sensitive girls and women is occasionally relieved by this remedy. Nervous headache and vertigo are often promptly relieved by valerian or the ammonium valerate.

Valerian has been favorably recommended in both diabetes insipidus and diabetes mellitus.

Contraindications. - There are no special contraindications to the use of antispasmodics other than in acute inflammations of the gastro-intestinal tract, when camphor should not be employed.

Administration. - Any of the preparations of the various members of this group may be used. Asafetida and camphor in substance should always be given in the form of pills or capsules. Camphoric acid is best administered in capsules.