Syn. Cream of Tartar.

Having been particularly described under the cathartics, this salt requires here no further consideration than in relation to its properties and uses as a diuretic. Judging from my own experience, I should be disposed to place cream of tartar at the very head of this class of medicines. Though there may be cases of dropsy which digitalis will cure, and this medicine will not, and others in relation to which the same observation may be made of squill, yet, on the whole, no one medicine, and I think no combination of medicines, will be found to cure so large a proportion of dropsical cases as the one under consideration.

When given in small and frequently repeated doses, so as not to purge, cream of tartar operates as a diuretic, and often very powerfully so, at the same time producing a refrigerant effect on the system. The salt under these circumstances is absorbed. in general, when the neutral salts of the vegetable acids are taken into the stomach, it is believed that the acid is decomposed, and the base exists in the blood, and is thrown off by the emunctories, as a carbonate, or a chloride, or in some other form of mineral combination. But, according to Wohler, this is not always the case with acidulous or super-salts, at least with the bitartrate of potassa; for tartaric acid has been found in the urine some time after its administration, and it is highly probable that it enters the circulation in part as the bitartrate. in this way, we may account for its extraordinary diuretic powers; for, were it merely by conversion into a carbonate or chloride that it operates, one of these salts ought to prove equally effectual.

Cream of tartar may be given in all varieties of dropsy, when not forbidden by the existence of an exhausting diarrhoea. Though theoretically applicable more especially to the febrile and inflammatory forms of the disease, I have found it not less effectual in those of a contrary nature, as, for example, that which so frequently follows miasmatic fever, after the disappearance of the febrile disease. it might be supposed to be contraindicated by debility; but I have used it as often in the feeble as the strong, and with not less success. in cases of debility, however, it must be accompanied with tonics and a nutritious diet, to counteract its depressing effects.

Much depends, for success, upon the manner in which the medicine is administered. if given in rather large doses, at long intervals, it will be apt to purge, and not to act as a diuretic, or but slightly; and it is upon its diuretic, and not its cathartic powers, that the chief dependence must be placed in dropsy. Yet it is a mistake to give the salt sparingly. I have noticed that half an ounce, in the course of the day, is generally insufficient to produce any beneficial effect. Less than an ounce in twenty-four hours will seldom answer; and it will not unfrequently be necessary, before it can be brought to act efficaciously, to give an ounce and a half, or even two ounces, in the same length of time. I have often given the latter quantity for many days successively; but have never exceeded it.

The plan which I usually follow is to direct the whole quantity that is to be taken in twenty-four hours, say from three-quarters of an ounce to two ounces, to be put, with a pint of water, or of strained juniper-berry tea, into a bottle; the mixture to be thoroughly shaken when used; and all of it to be taken in the time specified, in small doses frequently repeated. The smaller the dose, and the more frequently it is given, the more effectual it will probably be. Not more than a wineglassful should be taken at once; and this may be repeated every two hours. The direction thoroughly to shake the bottle is important, as otherwise the patient will be apt to drink only the supernatant liquid; by far the larger portion of the salt remaining undissolved at the bottom. The juniper tea is an excellent adjuvant, not so much for its diuretic action, though this is often considerable, as for its stimulant influence on the stomach, which obviates the depressing effect of the salt. The caution should always be observed, to cause the infusion of juniper to be made separately, and to be strained before the salt is added, as otherwise the undissolved salt and the bruised berries would be mixed together at the bottom of the vessel, and much of the former would probably be thrown away. The young reader must remember that cream of tartar is of very difficult solubility in water. Should the medicine purge more than once or twice in the day, unless purgation is aimed at, it should be restrained by opium, so as to prevent it from being carried out of the system, and thus escaping absorption.