The diet is especially important in eruptions due to poisons such as green food, distillery refuse, silage, roots, ergoted or smutty food, musty fodder, irritant plants in hay or grain feed, buckwheat, etc. In many cases a change to sound fodder and a laxative to clear the alimentary canal of the irritant, may be all that is required. In cases where the feeding has been parsimonious, a judiciously gradual change to a generous diet may be required. Again when the feed has been unduly rich, or spiced as in the patent food for stock or the table leavings for dogs, a plainer, simpler and less exciting diet will be called for. Indigestions, urinary and hepatic disorders due to diet may be often corrected by a more judicious ration.
Rest is a most important element in horses and hunting dogs. When pressure of the harness keeps up the irritation, or when active movement reopens cracks in the tense rigid congested skin of the heel, carpus or tarsus of the horse, the parts must be kept quiescent. When on the other hand chaps and fissures are caused and maintained by stocking, the patient may do much better with exercise. In skin congestions which are aggravated by work and increased cutaneous circulation, rest is imperative.
Cleanliness is no less imperative. Many cases are started and maintained by filth on the skin and in the air of the stable and hence sponging, currying, brushing, rubbing, are directly therapeutic. Yet care must be taken to avoid irritation where the skin is tender. In the sensitive heels of the horse congestion, chaps, and stocking are often determined by washing in ice cold water and leaving to dry uncovered, in a draught of air, or by washing with common laundry soap having alkali in excess. Even tar soap will sometimes keep up the trouble in a specially sensitive skin. Apart from such exceptional conditions, thorough grooming is commendable, not only in cleaning the skin, but in improving its circulation and nutrition.
Diuretics are often beneficial in eliminating from the system the irritant products generated from disorders in sanguification, digestion, urinary secretion and hepatic function, as well as those that are derived from the cutaneous disorder. They tend further to reduce any existing fever, and to cool and relieve the burning integument. The alkaline diuretics are often very useful.
Purgatives act in a similar way and are especially indicated in cases due to ingested irritants, and in such as depend on morbid products of gastro-intestinal or hepatic disorder. In many acute attacks these may be said to be almost specific in their action as in urticaria, and in the eruptions due to distillery products or green food.
Tonics are often called for to correct dyspepsias, to improve the general health and vigor, the sanguification and nutrition in weak and debilitated conditions. Iron, cod liver oil, bitters, quinia, quassia, calumba, gentian, nux, are often of value in such cases.
Alteratives. Arsenic may be said to act as a tonic with a special tendency toward the skin where it affects the epidermis and epidermic products and is applicable to many subacute and chronic disorders, as psoriasis, acne, dry eczema, and pemphigus. It has been further supposed to be most useful in superficial lesions, and in those due to a neurotic origin, from the known operation of arsenic on the nerves. It is little suited to acute skin diseases, and though often valuable is not to be trusted as universally applicable.
Sulphur is often useful as a laxative, but also as a stimulant to the cutaneous secretions when these are impaired.
Antimony is similarly a cutaneous stimulant and is sometimes useful in chronic inactive conditions.
Phosphorus has been found useful in obstinate cases and probably acts on the nerve centres in improving nutrition of the integument.