In November of 2015, researchers announced finding that the erectile dysfunction drug Viagra may help to prevent diabetes in at-risk patients. The study followed 42 patients identified as pre-diabetic and tracked their progress over the course of three months, during which time each patient took either Viagra or a placebo. At the end of the study period, those patients randomly assigned to the Viagra group showed higher levels of insulin sensitivity, as well as lower levels of a marker that indicates a risk for heart and kidney disease.
The lead author of the study, Dr. Nancy Brown, and her co-authors have hypothesized that the results stem from Viagra's ability to block an enzyme that breaks down the blood vessel relaxant cGMP. Higher levels of this compound then support smooth muscle relaxation, vessel dilation, and improved blood flow. Scientists have indicated the need for further and larger-scale research, which would help to determine whether similar drugs would be appropriate diabetes preventives.