Health & Fitness Viagra Might Stop Cancer From Spreading, But Do Not Raid The Bedside Drawer Yet By(DNA/AI Illustration)A study published in Cancer Research found that sildenafil, the drug sold as Viagra, made it harder for cancer cells to spread. Cancer cells need cholesterol to break away from a tumour and travel. Men taking sildenafil showed improved five-year survival. One Warning Worth RepeatingDo not start taking Viagra because of a headline. If you are on cancer treatment, or thinking about ED medication at all, that conversation belongs with your doctor.