Medical properties and uses.-Digitalis is directly stimulant, indirectly sedative2, and diuretic. It at first quickens and fills the pulse; but afterwards weakens the force of all the vital functions; and, by a proper exhibition of it, the frequency of the pulse may be diminished any number of pulsations, and regulated at the pleasure of the practitioner; whilst at the same time it admits, to a certain extent, of the employment of such medicines as increase the firmness of the arterial action, and give tone to the habit. When given to the full extent of which the system can admit, it is apt to accumulate; the pulse intermits; and vertigo, indistinct vision, and nausea with vomiting or purging occur; and if, after these indications, the quantity be still increased, or if any considerable portion of the recent herb be inconsiderately swallowed, it produces delirium, hiccough, cold sweats, convulsions, syncope, and death. It is supposed to quicken the action of the absorbent system; but although the discharge of urine is very considerably increased during its use, and the load of water with which the body is oppressed in dropsies be thrown off, yet it is not easy to conceive how it can operate on the absorbents; and therefore the modus operandi of foxglove, in producing its diuretic effect, may be regarded as still unexplained3, although it must probably operate as a direct stimulant to the kidneys.

As a sedative, foxglove was early used in some acute diseases, but its powers were not understood. It is employed in inflammatory diseases; in active haemorrhages, particularly from the uterine vessels, when the pulse is sharp, throbbing, and frequent; in scrofula, and in most cases of increased vascular action, or in which it is essential to lessen the usual impetus of the blood, as in aneurism; but in such cases it should be administered in doses sufficiently large to induce, rapidly, its sedative influence. In mania it acts as a narcotic, soothing the nervous system and procuring sleep to the patient. The tincture is the best form of administering it in this disease; and the dose may be carried to an extent far; beyond that which can be prescribed in any other disease. (See Tinctura Digitalis, Part III.)

1 Bib. Univ. xxvi. p. 102.

2 This terra implies, as I understand it, any substance which diminishes the action of the heart and arteries, without first increasing it.

3 Dr. Baildon observed a curious effect of posture in ascertaining the real effects of digitalis on the pulse. When, by gradually increased doses, he took it to the extent of grs. vj. in the day, the pulse fell to 40 from 110. But when it was actually at 40, the erect posture would raise it to 100; when sitting, it was 72; and when lying down, 40. He observed the same effect in several patients to whom he gave it.-Edin. Med, and Surgical Journal, iii. 271.

It was prescribed in phthisis so early as 1710; and great praises were bestowed on it by a writer of that period.1 Dr. Ferrier found its utility in this complaint much increased by combining it with myrrh and sulphate of iron2: but it has often proved hurtful in the early stage of the disease. Its use has also been extended to venereal ulcerations, chronic rheumatism, hooping cough, and some spasmodic affections. As an external application, it has long been used in Italy3 to cleanse all sores; and Hufeland recommends it to be used in the form of fomentation for dispelling glandular swellings.

As a diuretic, the use of foxglove was re-introduced by Dr. Withering in 1775.4 He found that its beneficial effects in dropsies were more certainly obtained in those constitutions in which there is a laxity of fibre,, pale countenance, feeble intermitting pulse, and cold skin; and where the swelling easily pits. But in florid habits, with great strength, tense fibre, and hot dry skin, no diuresis follows. "If the belly in ascites be tense, hard, and circumscribed, or the limbs in anasarca be solid and resisting, we have but little hope."5 Experience has confirmed these judicious observations; and it is found that where this favourable state does not exist, it should be produced by bleeding, and the free use of neutral salts, and calomel, before Foxglove is administered. The diuretic effect is checked when much nausea is present; and Withering says purging also checks it; but I have not found this to be the case. The kinds of dropsy in which its influence is most useful, are ascites, anasarca, hydrothorax, and that species of swelling which succeeds parturition, phlegmasia dolens, where the legs and thighs swell, become pale and semi-transparent, with pain in both groins, depending on inflammation of the veins.

It has also been found of the greatest service, when conjoined with nitrous acid, in the dropsy which occurs in broken down constitutions, that have been long harassed by mercury.6 Digitalis will not cure a dropsy attended with palsy, unsound viscera, or other complications of disease; but by allaying the urgency of the symptons, it gains time for other medicines to act. No benefit has hitherto been obtained from its use in hydatids, ovarian dropsy, or in hydrocephalus.

1 Salmon. See The Edin. Med. and Surg. Journal, v. 303.

2 Essay on the Medical Properties of Digitalis.

3 Aralda (Digitalis) tutte piaghe salda.

4 He was induced to try it from finding it the active ingredient in a family recipe for the cure of dropsy, regarding which his opinion was asked.

5 Withering's Account, etc. 186.

6 Carmichael on Diseases which have been confounded with Syphilis, 4to. p. 03-5.

Foxglove is administered in substance, or in decoction, or in the watery infusion, or in tincture, (see Preparations). When given in substance, it is frequently combined with aromatics, soap, or ammoniacum; and most advantageously with calomel and opium, when it is required only to produce its diuretic effect. It is always proper to begin with a dose not exceeding gr. j. of the powdered leaves, given in a pill twice a day; and gradually to increase it till its effects are apparent either on the kidneys, the stomach, the pulse, or the bowels. The medicine must then be discontinued; but in dropsy it may be repeated after an interval, if the whole of the water be not evacuated. During its employment, diluents are useful and necessary; and immediately it is discontinued, the strength should be recruited by generous food, steel, and cordial tonics. The deleterious effects of an overdose are to be counteracted by cordials, as brandy, mint tea, and opium; and when these are not sufficient, by blisters.

When the dose has been given a short time only before medical aid is required, the decoction of yellow cinchona bark should be used with the stomach pump, instead of water.

Officinal preparations.-Decoctum Digitalis, D. Infusum Digi-talis, L. E. Tinctura Digitalis, L. E. D.