Big pharma has a billions/trillion dollar foothold in the medical community. With ADs, when the patent runs out, then they manipulate a molecule or two and viola, a new AD drug to garner billions from the drug pipeline- i.e. Celexa to Lexapro.
All that aside, I was on Paxil and Celexa for a total of 5 years. The sides effects getting on SSRIS were horrible, but within 6-8 weeks my anxiety went away and I had no more panic attacks. I did gain over 50lbs during the period I took ADs and was starting to develop other health issues. I tapered off for a couple of months and the withdrawals were horrible.
SSRIs are very effective for most people as they certainly were for me (other than the weight gain). However, I personally were never go back on them. I employ other methods to deal with my anxiety disorder, PTSD and bouts of depression. It's hard work, but just as effective in the long run. That's my opinion.