Bismuth Subsalicylate

Bismuth subsalicylate, with a nominal chemical formula of C₇H₅BiO₄, is a colloidal substance obtained by hydrolysis of bismuth salicylate (Bi{C₆H₄(OH)CO₂}₃). The actual structure is unknown and the formulation is only approximate. Recent evidence indicates that it is composed of a bismuth oxide core structure with salicylate ions attached to the surface. A model structure has recently been published having the composition Bi₃₈O₄₄{C₆H₃(OH)CO₂}₂₆. It is a drug used to treat temporary discomforts of the stomach and gastrointestinal tract, such as diarrhea, heartburn and nausea. Commonly known as pink bismuth, it is the active ingredient in popular medications such as Pepto-Bismol and, since 2003, in Kaopectate.