Vitamins - B3 - Contraindications / Precautions / Warnings

Do not take B₃ if you have a liver disorder, gout, or high blood pressure (due to its dilating effect on blood vessels -- see below).

Do not be alarmed if you experience a niacin flush -- a dilation of blood vessels combined with histamine release from your mast cells. This results in redness and tingling around joints, certain muscles and other portions of your body, flushed face, and increased warmth. Depending on dosage, the effect can last from several minutes to an hour. The effect is completely normal, though you may be caught off guard at first -- especially if you do not know it is coming.

Nicotinic acid is the component that causes the niacin flush. If the flush becomes a nuisance, use the niacinamide form of niacin instead.

Do not exceed 150 mg total daily dosage, unless under the supervision of your naturopath, nutritionist, or other health practitioner.