You really want to get new meds cause the withdrawl gets worse! I've been there. It wasn't pretty.
I agree with mammo, Citalopram which is the generic of Celexa is almost identical to Lexapro. Lexapro is just a newer version of Celexa. Stopping anti-depressants cold turkey can cause severe withdrawal symptoms. I took it for a while and it only cost 4$ at Target.
There are many very good generic antidepressants. Call your doctor immediately, explain why you had to stop and ask for one to be prescribed for you. He knows you're not to stop this medication cold turkey, and doctors have become very understanding with today's economy that a lot of us cannot afford the brand names. I take a generic and it's works great! A month's worth will cost between $8 and $10. Take care.