Zoloft probably has the best record for working on anxiety, but it has a reputation for more side effects than
Lexapro and a reputation for being harder to
quit, though nothing comes close to the difficulties of Paxil. Possible side effects are vast -- from your headaches to weight gain to personality changes -- you're dealing with the brain here -- so if you know you tolerated Lexapro well and can't solve the problem without medication, maybe that's the best way to go.