Topamax and heart problems

I was on 50 MG of Topamax and 1/2 Phentermine tablet for 3 months as part of a physician's weight loss program. In that time I lost 38.1 lbs (had little appetite, but had lots of energy and exercised by walking over 1 hr every day or every other day....depending). One week after my 3-mo weigh in, I started experiencing heart problems during one of my walks. I felt dizzy, I was sweating more than usual, I was lethargic and I just didn't feel "normal." The next morning I felt good so I went for my walk. The problems from yesterday intensified during my walk and I had to quit after 1 hr. I was very dizzy, sweating a great deal, I was very lethargic and I was nauseous. It also felt as though my heart was jumping out of my chest (palpitations). I went home and couldn't get out of the chair; that's how tired and bad I felt. That afternoon, I drove myself to the doctor. My blood tests and urine screen were "normal," but my EKG (on-site and immediate) was abnormal. I have always had "irregular EKG's" due to what I call "an extra beat." But this time my heartbeat was "enhanced" and not "normal" for me (doctor's words). The chart showed that I was having many palpitations (strong, irregular ones). I was told not to walk and not to leave town over the holiday weekend (the doctor still didn't believe the medicine was to blame since I had been on both over 3 months). I stayed inside much of the weekend, but finally went to a store to return an item. After 10 min in the store, I felt HORRIBLE (worst ever). I was so dizzy, very nauseous, I was sweating (in a very cold store), my heart was jumping and it was difficult to take more than a few steps. I went home and spent the remainder of the weekend in the house. On my own (2 days later), I cut the Topamax in half and took the usual 1/2 pill of Phentermine. I started feeling better that same day. The next day I did the same w/ my mediation and felt MUCH better (although not 100%). On day 3, my doc phoned me at home. When I told him I had cut down on my Topamax and felt much better, he told me to immediately stop taking BOTH drugs. I did and I improved daily. On day four I was 100% better. After a week and 1/2 of overeating (and being depressed about it), I began taking 1/2 tablet of Phentermine (but no Topamax) w/o my doctor's knowledge. That was 3 days ago. I am feeling well with an occasional palpitation (minor though). I am back to having little appetite. I see my doctor in 2 days. He may be unhappy that I put myself back on the Phentermine, but at least now I KNOW that TOPAMAX was what caused the majority of my heart problems. I am not sure what my doctor will do (probably demand I stop taking the Phentermine); I am hoping he will place me on a safer drug that will help me reach my goal of a total weight loss of 100.5 lbs. I have been overweight for 18 years (since my marriage) and I am FINALLY determined and motivated to lose weight by eating less, eating right and exercising. PLEASE be aware of taking Topamax!