Transient receptor potential canonical 6 (TRPC6) is an important mediator of pathological hypertrophy and fibrosis, contributing to renal and cardiac disease. However, no selective TRPC6 inhibitor with in vivo efficacy has been developed and tested to determine if nongenetic channel suppression ameliorates disease in intact animals. We developed and tested an orally bioavailable TRPC6-specific inhibitor, BI 749327, revealing its capacity to improve cardiac function and reduce chamber dilation and fibrosis in the context of abnormal hemodynamic stress. Similarly, BI 749327 suppressed myofibroblast activation and fibrosis in a renal disease model. These data support BI 749327 as a representative of a therapeutic class for treating cardiac and renal disease and provide a tool for studying the biological function of TRPC6.