A small daily dose of the popular erectile dysfunction drug Viagra may significantly reduce colorectal cancer risk shows a study in mice. Viagra cut in half the formation of polyps an abnormal and often asymptomatic clump of cells on the lining of the intestines that may become cancer said the study published in the journal Cancer Prevention Research. Next steps should include a clinical trial for the drug in patients considered at high risk of colorectal cancer such as those with a strong family history multiple previous polyps and chronic intestinal inflammation like colitis said corresponding author of the study