Mercury and lead are absorbed from the bowel in considerable quantities, and are capable of inducing acute irritant poisoning as well as chronic poisoning.
After the irritant has been removed either from the stomach or intestine, a feeling of irritation of the mucous membrane may remain, and sickness, diarrhoea or pain may continue in the stomach and intestine although the irritant is no longer present within them, just as the flow of tears and desire to rub may remain in the eye after the piece of grit which has occasioned it may have been removed.
In some abdominal conditions, for instance, opium is still preferred by the majority of practitioners, though certainly not in gastric cases, where morphine gives the relief for which opium often increases the need, owing to the irritant action of some of its constituents.
When salicin is taken internally no irritant action occurs, nor is there any antisepsis.
It acts as a rubefacient, an irritant and a counter-irritant.
If it be absorbed from a surgical dressing there are no irritant symptoms, but when the acid is swallowed in concentrated form, symptoms of gastro-intestinal irritation occur.
For external use, sulphuric acid is a powerful irritant and caustic, acting by its powerful affinity for water and therefore dehydrating the tissues and causing them to turn black.
The condition which remains after the irritant has been removed is one of inflammation more or less intense.
Though ammonium chloride has certain irritant properties which may disorder the stomach, yet if its mucous membrane be depressed and atonic the drug may improve its condition, and it has been used with success in gastric and intestinal catarrhs of a subacute type and is given in doses of io grains half an hour before meals in painful dyspepsia due to hyperacidity.
The salt is a corrosive irritant poison when taken internally.