work nights tried low dose sleeping pills

I work night and even on my nights off i can't sleep more that 1 or 1 1/2 hours. When I sleep during the day it is worse. I am curious as to the strongest Canadian sleeping pill that is available with perscription so I can ask my doctor about it. I tried herbal stuff and nothing helps. The lack of sleep is dong something to my moods and my family life doesn't exist anymore