Xanomeline and Trospium: A Potential Fixed Drug Combination (FDC) for Schizophrenia-A Brief Review of Current Data.

Xanomeline, a cholinergic agonist, was initially evaluated for the treatment of Alzheimer's disease and schizophrenia. However, drug development was stopped due to the severe cholinergic adverse effects. In recent years, xanomeline has been explored, along with trospium, a peripheral cholinergic antagonist, for schizophrenia. Xanomeline acts primarily as an M1/M4 agonist and might lead to improvement in all symptom types of schizophrenia. Due to its role as an antimuscarinic agent, trospium is expected to reduce the adverse effects of xanomeline. In initial studies, this combination seems to be promising in the treatment of schizophrenia. The most common side effects of this combination included constipation, dry mouth, and nausea. This article summarizes the present status of combination xanomeline and trospium in schizophrenia.