If I was given the wrong prescription instead of antibiotics I was given a psycotic antidepressant, do I have a case?

Yes, assuming a real mistake was made either by the MD or the pharmacy.  You will also need to establish that you suffered "damages", e.g. became sicker because you weren't on antibiotics or suffered bad side effects from the anit-psychotic (the name of which you need to establish as well as its character.  If you can show (money) damages, call me at 310-271-0606 or email me at bfeigen@feigenlaw.com.  Brenda Feigen