admin in Viagra Pills: Viagra has been tested and found effective for diabetes in men. Viagra works by helping to weaken the smooth muscle of the penis during sexual stimulation, allowing increased blood flow. In previous studies involving 21 patients, the use of Viagra to improve the quality of erections in 48% receiving doses of 25 mg and 52% of those receiving 50 mg. Larger study of 268 men with diabetes found improved erections in 56% of Viagra. For comparison, between 65% to 88% of men reported improved without diabetes.