anxiety
"I was prescribed this for anxiety, depression and sleep problems (with my fibromyalgia)  after several trial and errors with other medication. I've been on it for three weeks now and it has no effect whatsoever on me. The doctor took me off sertraline and replaced it with mirtazapine.  I sleep about 3/4 hours every other night so I've doubled my dosage from 15mg to 30 mg after reading people's comments. I took the dose 3 hours ago and nothing :( hope it works better for others! (Uk)"