All depends on the LD. If I accomplished a goal it can last a loooooong time. Right now I am still feeling pretty good about my fighting lucid that I had a few days ago.
http://www.dreamviews.com/general-lu...ml#post2090967

Not really a high anymore, but definitely feel great about it still.

If I have a really aware lucid I normally feel good till the next night. Not very aware lucid has little or no effect anymore :/