This section is from the book "A Treatise On Therapeutics, And Pharmacology Or Materia Medica Vol2", by George B. Wood. Also available from Amazon: Part 1 and Part 2.
Rhubarb was known as a medicine so early as the times of the Emperor Justinian, and probably long before. its practical uses are such as might be inferred from the account above given of its properties. Whenever an indication for the evacuation of the bowels is conjoined with a debilitated state of the digestive organs, or considerable general debility, rhubarb may be used with propriety, especially if, at the same time, it should be desirable that no disposition to looseness be left behind.
It is the laxative beyond all others adapted to the constipation of dyspepsia. While it gently opens the bowels, it tends rather to invigorate than further to weaken digestion, and, though followed, after each operation, for a time, by a tendency to costiveness, it does not appear to exhaust the susceptibility to its influence, or at all events, does so very slowly; for I have known patients to use it habitually as a laxative for many years, without being under the necessity of materially increasing the dose Upon the whole, it appears to me to be the best substitute in our possession for the normal agencies which sustain regular alvine evacuations, and to maintain a condition of the alimentary canal nearest to that of health. in cases of habitual constipation, the best period, I think, for administering it, is at bedtime, so that it may operate in the morning. it is very frequently associated in dyspepsia with a little blue mass, when the liver, as often happens, is torpid; and, if there is peculiar insusceptibility of the lower bowels, it may be advantageously combined with aloes.
* Dr. E. Hardy detected the colouring matter of rhubarb in the urine on the 14th minute after swallowing 15 grains of the medicine; and at the 17lh minute the colouring was intense. The experiment was made on a patient affected with ectropy of the bladder, so that, by the introduction of a small tube into the ureter, the urine could be examined almost at the moment of its secretion [Journ. de Pharm. et de Chem., 3e sÚr., xliv. 158, a.d 1803.) - Note to the third edition.
In diarrhoea, when there is an indication for cathartic effect, rhubarb often answers well from the self-limiting property already referred to, as also for the somewhat astringent effect of its tannic acid, to which indeed that property may be reasonably ascribed. it is often combined with magnesia, when there is acidity in excess. To cases in which there is high irritation or inflammation of the alimentary mucous membrane, it is not so well adapted; and, in such cases, it should give way to castor oil. it appears to prove especially useful in the bowel complaints of infants, in which it is much employed.
There is sometimes occasion for a cathartic effect in chronic dysentery, in order to keep the upper bowels free. in such cases, rhubarb may be chosen, when the state of system is so much debilitated as to require support instead of depletion.
In the advanced stages of most febrile diseases of a typhous or malignant character, rhubarb often operates most usefully, removing the irritant or depressing feculent matter, without in any degree debilitating, but, on the contrary, rather strengthening the patient.
So also in scrofulous diseases, atonic gout, old paralytic affections, and, indeed, all complaints of debility, rhubarb may be employed with propriety, whether habitually or occasionally, as the case may require.
It is contraindicated in acute febrile and inflammatory affections, with a sthenic state of system; though, combined with calomel, it seems to lose in some measure its peculiarities, and acts with much energy. A dose of calomel and rhubarb is not unfrequently administered, with good effect, at the commencement of bilious fevers, and other acute affections involving the liver.
As a local remedy, rhubarb has been applied to indolent ulcers, being sprinkled in the form of powder over the surface.