For the record, melatonin is not an herbal extract. It is a hormone that regulates sleep cycles, and is normally secreted by the pineal gland.

I'd go with excercise. Certain types of antihimines are effective (as Susan mentioned), and antidepressant can help keep you asleep once you got there. Your best bet is to talk it over with your doctor if it's a continuing problem. I've had occasional problems after having no trouble most of my life. I think my metabolism was going batshit.