depression
"I have suffered from anxiety and depression for much of my adult life.I have tried almost every option & medication available. 
My first experience of Sertraline was just over 2 years ago,it was a breath of fresh air,& I felt fantastic.My happiness & quality of life improved beyond recognition.Despite being sceptical, I stuck with 100mg dose(8mnths),& continued to feel the benefits.
Due to my new found joie de vive I decided to give up on the treatment. Unfortunately after a month or so I noticed a change in my feelings,& gradually became more and more withdrawn.This trend continued. 
3 months ago I started on Sertraline again, & it's been just as amazing. Incidentally I was also found to be gluten intolerant which can magnify depression"