MATERIA MEDICA. The signification given to this term by different authors has varied very much indeed, some employing it to denote the whole range, and others only a particular department, of that branch of medical science which relates to the means employed for the prevention or in the treatment of diseases. Prophylactic or preventive and remedial or curative means may be re-
ferred to three principal divisions; 1st, the performance of manual operations; 2d, the regulation of what have been termed the non-naturals, as of diet, exercise, temperature, clothing, &c.; and, 3d, the employment of medicinal substances. Manual operations, as far as their mode of performance is concerned, fall under the domain of surgery; the regulation of the non-naturals is the object of dietetics and hygiene. As to the third division, medicinal substances, they may be considered either in reference to the sources from which they are derived, or to the modes in which they are prepared for medical use; or they may be considered, along with the other two classes of means, in reference to the immediate purposes for which they are employed in the treatment of diseases, and the indications which they are intended to fulfil. Now, the term materia medica has by some been understood as embracing the consideration of remedies in all these respects. But by others, and, as we conceive, more correctly, it has been limited to signify the natural and commercial history of medicinal substances. Those processes by which medicinal substances are fitted for use constitute the department of pharmacy, whilst the purposes for which remedies are employed form the objects of consideration in therapeutics. Some have employed the word pharmacology as a general term, to include the whole of the knowledge that has been obtained relative to remedies.
The natural and commercial history of medicinal substances, materia medica properly so called, and the means by which they are rendered fit for internal administration or external application in the treatment of diseases, or pharmacy, are subjects of great importance to the medical practitioner; but it would scarcely be possible to render them interesting to the general reader, and we are unwilling, therefore, to occupy our pages in their discussion. The case is different, however, in regard to the action of
remedies upon the human economy, or therapeutics. It is, we think, of great importance that the public generally should understand what are the immediate objects which medical practitioners propose to themselves to effect by the administration of remedies in the treatment of diseases, or the changes in the morbid actions of the economy, by which they endeavour to restore it to a healthy condition. The want of accurate notions on this subject is the source of much of that encouragement which quackery receives, whether practised by irregular or by regular practitioners, and which unfortunately is by no means confined to the less educated classes of society. Under the article THERAPEUTICS, therefore, we shall endeavour to give a popular view of medical indications, and of the means by which they may be fulfilled.
MATERIAL denotes something composed of matter, in which sense the word is opposed to immaterial. See METAPHYSICS.