Preventing nighttime urination with saw palmetto?

As far as I know, palmetto might be helpful with prostate problems, when the prostate is enlarged or if there is a case of benign prostatic hyperplasia. So, it could also be helpful with your problem too. Still, you might consider trying to sleep a bit more, it is known that lack of sleep might induce some conditions, stress increase especially.

Well,

First of all why do you sleep only five hours? This is a habit or you don’t function well if you sleep longer? It is a known fact that lack of sleep can be serious problem and sometimes it can increase amount of stress significantly. This is not good for your organism because being under constant stress can have severe consequences for your health.

If you want to deal with your problem in a proper way than you should consult your GP. First of all tell him about your concerns and wait for his opinion. if he believes that you should use saw palmetto for your problems than ok, but somehow I believe there is a better way to help you.