So I have been through a tough time with medicines, I went through severe anxiety again lately and went to fluoxetine the first time from March-June and it gave me severe anxiety still. Then I went on Lexapro for 3 weeks (loved it) but the constipation was to much. Switched to Buspar for 5 days and I refuse to take it anymore. I just started Celexa today.Since I had SSRI's in my system. How long will this take?