My meds have insomnia as a side effect so I've been using melatonin for a while now Layali - I'm at 4mgs.
I had to see my Dr about it because you can;t get melatonin here locally without a script, but I always run supplements past my Dr anyway to rule out any nasty interactions with others meds etc.]
it works pretty well 95% of the time for me.
D