Temazepam
"I've had insomnia for 15  years and tried about everything on the market.  The only medicine which helps is 45mg of Temazepam. Lower doses did nothing. However, even that is good for only 4 hours sleep. I have to take them almost 3 hours before bedtime for them to work. There are at least 1/3 of the nights it does nothing.  I have had 3 sleep tests and no apnea has ever been detected. Antidepressants all made insomnia worse with frequent awakenings. 

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