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.
The most common side effects of niacin are: stomach upset, flushing, headache, reduced blood pressure upon standing (orthostatic hypotension), vomiting, diarrhea, itching and ; tingling sensations of the extremities. Flushing may be reduced by taking 325 mg of aspirin 30 minutes before the niacin and by increasing the dose of niacin slowly.