Erectile dysfunction: Viagra and other oral medications - Mayo Clinic

The four main medicines taken by mouth for erectile dysfunction are: Avanafil (Stendra). Sildenafil (Viagra). Tadalafil (Cialis). Vardenafil. These medicines are called PDE5 inhibitors. They enhance the effects of a chemical the body makes that relaxes muscles in the penis, called nitric oxide.

Sildenafil Emerges as a Candidate Drug for Alzheimer's Disease

69% relative risk reduction in large database analysis prompts plans for mechanistic and phase 2 studies. Sildenafil (Viagra®, Revatio®) shows promise as a candidate drug for prevention or treatment of Alzheimer's disease (AD), according to Cleveland Clinic-led research published in Nature Aging. Cleveland Clinic is a non-profit academic ...