Sorry you have to go this route. Does your doc think the symptoms post prostate surgery may resolve? Cialis relaxes the smooth muscles and arteries inside the penis. At the same time, it also increases blood flow to the penis. When aroused, this combination of relaxation and increased blood flow allows the penis to fill with blood, which results in an erection. It can be taken about 1 to 2 hours prior to full effect being necessary or at a low dose, can be taken every day. It lasts about a day and a half allowing you to get erections that whole time. However, as I'm sure your doctor told you, if you get an erection that lasts something like 4 hours, call your doctor and get medical attention. Once you start taking it, it will just allow you to function like you did prior. There 'can' be side effects though to watch out for. https://www.goodrx.com/blog/how-to-take-cialis-avoid-side-effects-and-get-best-results/ Have you taken it yet? How did it go?