URTICARIA, OR NETTLE RASH.
The first step in the treatment is to discover the exciting cause, which may be either some local irritant or an internal one. In the former case the task is an easy one: nettle or jelly-fish stings, mosquito bites, etc., are as a rule obvious. The internal causes are more difficult to detect, especially in the chronic cases, and one article of food after another must be omitted till the toxic agent is detected. In all cases a milk diet is clearly indicated, as this food is rich in Calcium Salts, as is also butter and spinach.
Fruits, especially acid fruits, should be prohibited, since they tend to decalcify the blood.
In the formidable or so-called giant urticaria the symptoms come on suddenly, often soon after a meal, so that the exciting cause may be at once suspected, such as shellfish, fungi, strawberries, raw apples or other fruit, pastry, pork, cheese, etc.
Reflex causes as ovarian irritation are also to be thought of in the search for the primary disturbing element, and dyspepsia and constipation should be remedied.
The treatment of the acute giant form with its alarming but for the most part harmless symptoms is best carried out by the administration of an emetic to rid the stomach of the food or fermenting matter which has probably been the origin of the attack. As soon as emesis has occurred a strong saline purge should be administered in order to expel from the bowel any unabsorbed toxic product.
In the rare form of \Villan's Urticaria tnberosa, where large hard tumours appear generally during the night-time in the vicinity of joints, similar eliminatory treatment should be employed, the saline purgative being preceded by a full dose of Calomel, and Calcium salts should be adminis tered in courses of short duration periodically.
In the more chronic forms, the main symptom being the feeling of intense burning itch, local remedies suggest themselves; these arc, how ever, as a rule most disappointing. The best of all applications is Bicarbonate of Soda in the warm bath, but as usually recommended the bath is useless. One writer on skin diseases after another advises that 4 oz. of the soda salt should be dissolved in a large bath (3o to 4c gallons of water). 2 lbs. may he advantageously employed. 4 oz. added to 3o gallons of water make a solution of about the strength of I gr. to oz., which can have no therapeutic action. The patient should lie for half to one hour in the stronger solution at a temperature of about QS° F.
Upon coming out of the bath the skin should be dried with a soft towel, and the portions which are the seat of the urticaria may be freely anointed with a r in 4o Carbolic Oil. Severe itching may he relieved in a limited
area by mopping it with Menthol, i part, dissolved in 3 parts of each of the following: Chloroform, Ether and Camphorated Spirit, making a in so solution of menthol. It is hardly necessary to say that such a lotion should not be swabbed on a portion of skin which has been deeply sera tch«I or excoriated by the finger-nails. r drachm of menthol dissolved in to oz. weak spirit may be freely sponged over large areas of skin, and so may ordinary Carbolic Lotion (t in 4o). Any of the sedative applications mentioned in the article on Pruritus may be tried. A favourite lotion is the following: 13, . Liq. Plumbi Fort. 5ij.
Ac. Acetici Dil. 5j.
Liq. Carbonis Deterg. 5ij. Ac. Hydrocyanici Dil. 5j. Aquce Destillatce ad 7,5'NVi Of drugs for internal use, save such as are indicated for the removal of the dyspepsia, gout, etc., there is no agent of any real or specific value save the Chloride or Lactate of ('alcium; there is always a diminution in the coagulability of the blood. 133 administering this drug the wheals and itching generally rapidly improve even when the primary error in the dietary remains uncorrected, and on withholding the lime salt the symptoms will return. Often the irritability of the skin remains for a considerable time after the exciting cause has been removed, but it speedily disappears under calcium administration. The lime salts prevent exudation from the vessels, and thus diminish the pressure on the sensory terminals. Either salt may be prescribed in 15 gr. doses in ) oz. water thrice daily.
In the urticaria of infants Lime Water or Magnesia added to the milk acts in a similar manner. Free elimination in all chronic cases should be maintained by stimulating the urinary secretion by a liquid dietary and he daily morning doses of a natural mineral water containing Sodium or Magnesium Sulphate. Gouty cases respond to similar treatment in combination with moderate doses of Salicylate of Sodium.
It must not be forgotten that in some susceptible individuals, iodides, salicylates, cubebs, copaiba and santonin may bring on an attack of urticaria, and this often follows serum treatment for diphtheria and other diseases.
In the infantile affection known as m•ticaria pigmentosa, calcium salts are of no avail; the raised pigmented patches always disappear before puberty, and the only indication for treatment is the slight pruritus, which may he relieved by any of the above-mentioned sedative lotions or by sponging with vinegar.