This section is from the book "Materia Medica And Therapeutics Inorganic Substances", by Charles D. F. Phillips. Also available from Amazon: Materia medica and therapeutics.
In irritative diarrhoea, with red tongue, nausea, heartburn, griping pain, worse after meals, and frequent ill-formed stools, I have found bismuth invaluable. In some persons, mostly women, such a condition becomes habitual, and even ordinary articles of diet may cause severe aggravation of symptoms; the constant use of this remedy, however, gives them the greatest relief, and enables them to take food with comparative comfort; much flatulence is often present, and sometimes the diarrhoea depends on irritation from the development of sulphuretted hydrogen (Chambers). Bismuth is then also very suitable, for it combines readily with that gas and absorbs it (Practitioner, 1869); sometimes charcoal, or aromatic chalk powder, or rhubarb, may be added with much advantage.