major depressive disorde
"This medicine has been an excellent tranquilizer. It seems to stop whatever negative thoughts I'm having, and flattens my mood.  It has a half-life of only 6-8 hours! I would recommend it for sleep, and episodes of severe mental illness, be it MDD, PTSD, etc..

Note: as a drug to be on all day, this should not be first line. It causes a lot of drowsiness and feelings of being drugged. Being on it a short time, through sleep or a bad episode, can dramatically improve your day."