Picture 1 â Sun Poisoning Rash. Source â prime health channel. When excessive exposure of the skin to the harmful UV rays of the sun causes an allergic reaction in the form of development of itchy skin rash and the reddening of the skin, one may be said to suffer from Sun Poisoning Rash.
Note that excess niacin intake can cause symptoms similar to an allergic reaction, including skin flushing, stomach redness and warmth, particularly of the face. Your physician may recommend allergy testing to determine if you have an allergy or symptoms of excess intake.
I am no doctor, no expert, but my initial guess would be you had a normal reaction to niacin and in addition to it you had an anxiety attack. I know for a fact that the touble breathing, lightheadedness, and dizziness can all be symptoms of an anxiety attack.