There's no reason to expect creatine to have any effect on erection. Creatine mainly maximizes the water volume in muscle cells, no claimed effect on bloodflow or anything that would affect erections. Two supplements that might have some effect are L-Arginine and gingko biloba. Arginine increases nitrous oxide in the bloodstream, which dilates blood vessels. Gingko iis a blood thinner that s touted as increasing bloodflow to the "extremities," which presumably would include the penis. Warning: My posts have not been evaluated by the FDA!