My 35 yr. old daughter has been taking celexa 20mg for depression, and it did not work very well for her. Her Dr. prescribed Wellbutrin XL 150mg to take instead. Should she wean herself off the Celexa and onto the Wellbutrin, or is it ok for her to just switch from one to the other. She also takes theophllin for asthma and lanoxin for SVT