There is a great difference in the susceptibility of different individuals to the poisonous action of lead - as may be verified in any large factory - and it is comparable to what has been noticed with arsenical wall-papers, etc. One attack of colic strongly predisposes to another, which may follow after a long interval from comparatively slight cause - thus, a man who had suffered as a house-painter, turned game-keeper, and got an attack long afterward from stirring shot in water with his hands (British Medical Journal, i., 1877).

Synergists

The depressing influence of lead upon the circulation is assisted by digitalis, ergot, veratrum, prolonged cold, etc.; its astringent action by metallic salts of copper and zinc particularly. The other metals, especially mercury, antimony, and copper, have a similar effect in lessening nutrition.

Antagonists And Incompatibles

Sulphate and carbonate of lime, carbonic acid, acids mineral and vegetable, alkalies, iodide of potassium, opium, albuminous solutions, and most vegetable astringents are chemically incompatible, and most of these may be used in the treatment of lead-poisoning. In acute cases, when the drug has been taken by the mouth, emetics or the stomach-pump should be used, and sulphate of soda or magnesia given in milk or mucilage. In chronic cases, alkaline iodide should be given internally, and sulphur baths should be used, containing about 7 oz. of sulphuret of potassium. During half an hour of bathing, frictions should be employed, and soap should be freely used afterward (Eulenburg). Electricity should be applied to the affected muscles- faradaism if it causes contraction, if not, the continuous current three or four times weekly for about a quarter of an hour, whether it induces contraction or no: in curable cases it will ultimately do so. Purgatives should be freely given. Fatty food is said to antagonize the development of plumbism in lead-workers, and a long prevalent colic in large lead-works at Birmingham was stopped by the free use of a "treacle beer," containing sulphuric acid (Lancet, i., 1860). Washing the hands before eating, etc., is important, and washing with petroleum is said to be prophylactic (British Medical Journal, ii., 1877).

Pilocarpin and amyl nitrite antagonize the increased arterial tension which occurs in chronic cases (v. p. 256).

Therapeutical Action (External)

Disinfectant Power

A solution of lead nitrate (Ledoyen's disinfectant) has been in use for many years, and acts by decomposing sulphuretted hydrogen, but has no other good effect; it is comparatively expensive, and its black precipitate is sometimes objectionable: Dr. Goolden has, however, recently recommended as applicable to many cases, solution of chloride of lead, although it also can act only on sulphuretted hydrogen. He prepares it by dissolving 1/2 dr. of powdered nitrate of lead in one pint of boiling water, and mixing this with 2 dr. of common salt in 2 gallons of water. The precipitate which falls is in part carbonate of lime, in part carbonate of lead, and the clear supernatant fluid is a saturated solution of lead chloride. This quickly removes the smell of foul drains, ship-holds, etc., and cloths wrung out of it, and placed about a room, neutralize organic emanations, e.g., from crowded assemblies, fetid suppuration, etc. It was used with much advantage on board the Thunderer after a gun-explosion (Lancet, ii., 1875, ii., 1876; British Medical Journal, ii., 1876, p. 323).