My Depression comes on strong after exposure to certain chemicals, mostly from the job site! However household toxins especially on the onset of winter and the heating systems are fired up Depression may return due to improper ventilation of venting and the closing up of doors and windows! If you have a faulty furnace , cookstove or devices using natural gas or heating fuel oils, Depression and anxiety can become extreme!! This may not be your particular problem ,but it is something you may consider! If I am exposed to any kind of cleaning chemicals also, especially chlorine(bleach), even cheap perfumes get to me causing headaches at first and depression and anxiety if prolonged exposure takes place! If I stay chemical free ,I stay depression free!I dont know if this helps but consider the possibilty of chemical exposure!