insomnia
"Took Ambien for years but noticed increased short term memory problems, so I switched to Belsomra. Not the same kind of sleep you experience with Ambien. Took about 10 days for me to get used to this one because of the difference. It more mimics how you used to feel when you naturally got sleepy, not a dopey kind of sleep. Also, if you don't sleep because you're an extremely anxious person, you will not find this one as effective. I don't sleep as sound on this one if I have a lot on my mind, worrisome things, versus I just can't sleep because I'm wondering if, for example, Tesla's ideas really will work :)"