Yes, meds can cause symptoms of bipolar, especially steroids--but usually for those who are prone to becoming
bipolar. I had steroids several times with no
bipolar symptoms before actually developing obvious hypomania later in life. BUT, you could be an exception.
Lamictal is fairly activating, which would explain the anxiety. Depacote is usually somewhat of a downer. Even if you did have bipolar, there are other medications to try that may not make you feel as crappy.