insomnia
"I have Parkinson's, which often has insomnia as a symptom.  Sometimes I could not get any sleep at all for three or four nights. True. I tried Zopiclone which gave me four hours sleep at doses of 7.5mg, but I felt yucky next day.  My GP recommended 30mg of amitriptyline per night which generally gives me five hours sleep and I feel OK the next day. This is a wonderful medicine which has improved my life."