Different drugs affect different parts, tissues and functions of the organism, but the final reason why one depresses and another excites, or one either heightens or lowers activity according to dose and circumstances, remains substantially unknown in spite of researches into drug affinity which seemingly push it further and further into obscurity.
The study of regions implies a discovery of the seat of the disease and of the remedies related thereto. A large number of drugs are known principally by their regional effects; many of them are imperfectly proven and crudely applied because their drug image is not well rounded out.
They are often prescribed for specific, antipathic, palliative or suppressive effects. This is especially, although not exclusively, true of the use of low potencies or crude drugs. In a general way drugs which affect the same or similar tissues bear a certain relation to each other and are differentiated through the mental sphere and the modalities. Each holds some other as its acute or chronic counterpart; the mental state of the one being generally the opposite to that of the other.
Baryta carb in common with Apis affects the lymphatic system, but their respective mental states are almost diametrically opposite. While the former stamps its dyscrasic character upon the mind and countenance, the latter is its acute complement. The Baryta carb, constitution takes on Apis symptoms when the lymphatics show the presence of a blood infection. Similarly the chronic Sepia patient displays Lachesis symptoms in the presence of alcoholism.