Sudden shortness of breath?

I've been experiencing palpitations and sudden quick shortness of breath...what could it be?

• I'm a 23 year old male with no past medical/surgical history. I do not take any prescription drugs; however, for the past 4-5 years, I've been taking the over the counter weight loss supplement called "Xenadrine." I took it for 3 years WITH the ingredient ephedra, and 2 years without it, after the FDA removed that ingredient. My weight went from 310 to 155, and recently up to 185 (i'm trying to lose 30 pounds but that's a whole other story). For the past few months, I've had a few very scary episodes of sudden shortness/loss of breath accompanied at the same time by a feeling in my chest as if my heart stopped for a split second. This does not happen when I'm active - it ONLY occurs when I'm at rest, such as when I'm sitting or laying in bed. There are no other symptoms, and it only happens about once or twice a week. What could this possibly be? I prefer answers only from healthcare professionals please, because I am not interested in uneducated guesses. Thanks.

• Answer:

  The ephedra in the diet pill can cause lasting effects on your heart, your best bet would be to go to your doctor, you will need an EKG to determine if you are in a normal sinus rhythm. Also, since it sounds like your symptoms are intermittent, it may be helpful to wear a monitor that records your heart rhythm, you can get one of these from a cardiologist. Central theme here is to go to your doctor. Most likely, because of your age it is something benign such as anxiety, however, because you have used a substance like ehedra, your risk for cardiac injury increases.