The dried leaves and stems of Datura alba, Linn., and Datura fastuosa, Linn.
Dhatúrá (Hind., Duk., Beng., Punj., Guz.), Umattai (Tam.), Dáthir (Kash.), Ummetta, Duttúramu (Tel.), Ummatta (Mal.), Ummatte (Can.), Attana (Cing.), Padáyin (Burm.), Kachubung (Malay). These are the native generic names of the Datura plant, the different species being distinguished by affixes denoting the colour of the flowers, white, purple, &c.
128. The white and purple varieties of Datura are common on waste places throughout India; they possess the same medicinal properties, and although the purple variety is generally regarded as the more powerful, there is no evidence of its being so. Although a valuable medicine, much caution is necessary in its employment; as in over-doses it acts as a powerful narcotic poison. A very useful preparation is a tincture made by macerating two and a half ounces of bruised Datura seeds in one pint of proof spirit (356) for seven days in a closed vessel, occasionally shaking; it should then be pressed, and filtered, and measured, and sufficient proof spirit added to make one pint. This tincture generally produces all the sedative and narcotic effects which could be expected from opium, besides effecting a great saving, opium being very expensive, whilst this tincture can be prepared at a comparatively small cost. The dose requires to be regulated in each individual case; it is better, therefore, to commence with small doses of ten or twelve drops in a little water, and increase them to twenty or thirty drops, according to circumstances. As a general rule, twenty drops will be found to be equal in effect to one grain of opium. One of the effects of Datura is to produce dilatation of the pupil; the eye should therefore be occasionally examined whilst this remedy is being administered, and should the pupil be found very large and dilated, it may be regarded as a sign that the medicine has been carried as far as it can be with safety, whether it has produced its other intended effects or not.
128β. In Datura we have an excellent, if not perfect, indigenous substitute for Belladonna [Atropa Belladonna, Linn., is an indigenous shrub, in the Western Temperate Himalaya, alt. six to eleven thousand feet; from Kashmir to Simla (Flora British India), and the Kuram Valley, Aitchison]—in the treatment of Cataract and other Diseases of the Eye. Its mydriatic (pupil-dilating) powers have been examined by Sub-Assistant Surgeon Tarra Prosonno Roy (Indian Med. Gaz., Sept. 1870). He first applied a portion of a watery extract of the leaves of D. alba around the eyes; the pupils became widely dilated, and continued so for two days. He next tried an alcoholic extract of the seeds of the same species prepared by macerating half an ounce of the seeds in four ounces of country spirit, evaporating the tincture to dryness on a water bath, and dissolving the residue in one ounce of water. Experiments made with this solution prove beyond a doubt its power of causing dilatation of the pupil when locally applied; the strength of this watery solution being, at a rough estimate about equal in power to a four-grain (to the ounce) solution of Atropine.
129. In Asthma, the dried leaves and stem cut small and smoked, like tobacco, in a pipe, afford in many cases great relief. In some the benefit is immediate and striking, in others it has little effect, and in a few it acts injuriously; its value in any case can only be ascertained by personal experiment, but it is worth a trial in all cases. When the leaves fail, the dried seeds, which are thought to be more powerful, may be tried. The earlier in the attack it is employed the greater are the chances of success; it has little effect when the attack has lasted for some hours. For a person subject to asthma, a good plan is to adopt the habit of smoking a pipe of it the last thing at night, whether an attack is threatening or not; at any rate, he should keep a pipe of it already filled, with the means of lighting it, by his bedside, so that, immediately on an attack commencing, he may use it. From ten to twenty grains of the dried plant is sufficient to commence with; it may subsequently be increased to thirty grains, but in all cases it should be immediately discontinued if it produces giddiness, a feeling of sickness, or any other unpleasant symptom. Serious, and even fatal, consequences have followed its incautious use, hence too much care cannot be exercised in its employment. In Chronic Coughs, where the cough comes on in violent paroxysms, and is hard and dry, with scanty expectoration, smoking Datura (ante) proves beneficial.
130. For Rheumatic Swellings of the Joints, Lumbago, Painful Tumours, Nodes, &c., Datura, locally applied, often proves most serviceable in relieving pain. There are four modes, in either of which it may be advantageously employed: 1. Poultice, made by bruising the fresh leaves into a pulp, and mixing them, with the aid of a little water, with an equal weight of rice flour, to the consistence of a poultice. 2. Epithem; which consists of steeping a few entire leaves in arrack or other spirit, and placing them, whilst wet, over the seat of pain, and securing them in that position by a bandage. 3. Fomentation; made by infusing the leaves in boiling water, in the proportion of one ounce to each pint of fluid, and applying as directed in paragraph 393. 4. Liniment; prepared by macerating, for seven days, one ounce of the bruised seeds in a pint of Sesamum or other bland oil, and straining. In addition to the above-named affections, these preparations, applied to the loins, are useful in relieving the pain attendant on painful or difficult Menstruation, and in some painful affections of the Uterus; in the latter, they may more advantageously be placed over the lower part of the abdomen. They also prove beneficial in relieving Neuralgic pains, especially of the Face; for this the liniment is best adapted, well rubbed in over the seat of pain, and along the space immediately in front of the ear, or rather, in the narrow space between the ear and the jaw.
131. In Tetanus or Lock-jaw, consequent on a wound, Datura is worthy of a trial in the absence of more effective agents. Poultices of the leaves, renewed three or four times a day, should be kept constantly to the wound, which should be further cleansed if covered with thick discharge or slough, by the process of irrigation of tepid water (395). The Tincture of Datura, in doses of 20 to 30 drops in water, may also be given internally three or four times daily. The dose must be regulated by the effect produced, but it may be continued, unless the spasms previously yield, till it produces full dilatation of the pupil with some degree of giddiness, drowsiness, or confusion of ideas, beyond which it is not safe to carry the medicine. If the spasms abate, i.e., if they recur at more distant intervals, and are less severe and prolonged when they do occur, the medicine, in smaller doses at longer intervals, may be continued till the spasms cease altogether; but if, under the use of the remedy, after it has produced its specific effects on the system, the spasms show no sign of abatement, no good, but perhaps harm, will result from continuing it. In addition to the above means, Datura liniment (130) should be well rubbed in along the spine several times daily. The patient should be confined to a darkened room and protected from cold draughts of air; the bowels should be opened, if necessary by turpentine enemas (364). The strength should be supported by strong beef-tea, or mutton-broth (413), by eggs, beaten up with milk, and by brandy-mixture (420) or other stimulants; if these cannot be swallowed they should be given in enemas, for which purpose not more than four ounces should be used at a time; larger quantities will not be retained. The treatment detailed in this paragraph is advocated from the success which has in some cases of Tetanus attended the use of Belladonna—a drug to which Datura bears a very close resemblance in its effects on the system: employed as above directed, it may be need with perfect safety, provided that the case is carefully watched, and the medicine diminished or discontinued on the full development of its physiological effects.
132. In cases of Guinea Worm, a Datura poultice (130) is said to be the most useful in relieving the pain, and hastening the expulsion of the worm.