When I was in my very early 20s I could take T3s with not reaction ( and no pain relief either)... Recently I've had wisdom teeth break upon "sprouting" because according to the dds, my mouth is too small to support that many teeth and needed to be removed but couldn't afford it. They began to break and decay from exposure causing your typical crippling pain. My husband had T3s and T4s but I decided to got T3 to start at a lesser dose. Even with half a pill the T3 caused dizziness, agressives vomiting, confusion, chest tightness and asthma attack like symptoms coupled with muscles locking and agressive shaking. A friend suggested I try the T4 and wouldn't you know I had no allergic reaction. How is this? Any one know??? My body has also obtained allergic reactions to 2 antibiotics on top of the ampicillain I was already allergic to, in a 4 or 5 year span. Why is my body becoming alergic or rejecting new things? But most importantly, what in the world is the deal with a severe T3 allergic reaction and nada with a T4?