Scientists have discovered that sildenafil—better known as Viagra—can improve symptoms in patients with Leigh syndrome, a rare and life-threatening disorder. Early results show stronger muscles, fewer seizures, and major quality-of-life gains, sparking plans for larger trials. Credit: Shutterstock Sildenafil, the active ingredient in Viagra, may offer new hope for people living with Leigh syndrome, a rare and severe childhood disorder. Researchers from Charité -- Universitätsmedizin Berlin,