Appellant, Diana Taylor, appeals from an entry of a final judgment against her in favor of appellees, Dr. Gary Mallow and the Institute for Medical Weight Loss, in a medical malpractice action against them. We reverse. Taylor filed her complaint for medical malpractice against appellees on May 4, 1998. The complaint included an opinion letter from Dr. Stephen Deutsch asserting the appellees’ breach of the accepted standard of care. The letter indicates that Dr. Deutsch was trained in psychiatry and psychopharmacology and was a member of the American College of Neuropsychopharmacology. It was alleged in the complaint that appellees treated Taylor for her obesity by prescribing “”pfen fen”” without considering her medical history, which resulted in an exacerbation of her mental condition. Appellees answered the complaint, denied the allegations, and asserted various affirmative defenses.