I need the Niacin that burns...Is it flush free or just Niacin flush?

Many forms. Niacin is notorious for flushing with itching in the skin about 10-20 minutes after taking the pill. It comes in many forms - none are truly flush free. But the effect is variable in each person. You may find one that does this minimally for you and all seem to lose this effect with continuous use of Niacin.