L-Hyoscyamine is a chemical compound, a tropane alkaloid it is the levo-isomer to atropine. Target: mAChR Hyoscyamine is a chemical compound, a tropane alkaloid it is the levo-isomer to atropine. It is a secondary metabolite of some plants, particularly henbane (Hyoscamus niger.) Hyoscyamine is used to provide symptomatic relief to various gastrointestinal disorders including spasms, peptic ulcers, irritable bowel syndrome, pancreatitis, colic and cystitis. It has also been used to relieve some heart problems, control some of the symptoms of Parkinson's disease, as well as for control of respiratory secretions in end of life care .