About four years ago, I had my first "panic attack". I was drinking my usual morning coffee while driving to work, when all of a sudden, I lost my peripheral vision - almost blacking out - then my whole body went numb within seconds. I thought I was going to die. I pulled over to the side of the road (barely) and slapped myself across the face and didn't even feel it. It was scary as hell. Ever since then, I haven't been right. I feel like every day is a dream and I have a constant chest tightness, like I’m starving for air and can’t get a deep breath. I’m constantly trying to yawn to get that refreshing deep breath, sometimes sending me into a hyperventilate state (this has only happened three times). Over the last four years, I have had sudden near syncope spells, without a racing heart beat and without the racing thoughts. I’ve gone through many doctors (neuro, endo, pulmonary, cardio, GP, etc.) only to find that I am slightly hypothyroid. My thyroid levels were just a little below from what they need to be, so I am on the lowest dose of synthroid. I have had numerous tests from tilt-table and EKG to spirometry and sleep study. I do not have asthma and I am not depressed. My GP finally put me on xanax (after going through all of the SSRI’s and SNRI’s) which helps only because it makes me relaxed - even more than I should be. My questions are these: 1) Could it be in fact anxiety even though I have never been an anxious person - as I am pretty laid-back and calm most of the time? I ask this because, like I stated earlier - I have badycardia (because of the hypothyroidism) and I am never in the “fight or flight” state when my symptoms occur - mainly around noon to three o’clock EVERY day. 2) Why is it that every time I have ANY type of stimulant (which I completely avoid anyway), it acts like an extremely powerful tranquilizer. If I take a couple sips of coffee, I instantly feel like I’m going to fall over dead, again, without the racing heart/mind.