I took it briefly when I was with a girl as I was recovering from my kidney transplant (2 years to this day was my transplant btw). I took it because I had a difficult time maintaining an erection at that time and it didn't feel any different from any other boner. Glad I didn't need to continue taking it because it gave me mild headaches as well. Really sucked popping one thinking I was going to get sex and then when I didn't, I had headaches for no reason.