Niacin has long been a popular supplement for cardiovascular health, but unfortunately it can sometimes have some unpleasant side effects. The most common is a flushing of the face that occurs approximately twenty minutes after use. This is due to histamine release from the mast cells as a response to the large amounts of niacin introduced into the system at once.
Due to these side effects, many people discontinue niacin use before reaching therapeutic levels. Sustained release niacin is a possible alternative, but it may cause liver enzyme elevation with very high doses.
No-Flush niacin, or inositol hexanicotinate, is not a sustained release of niacin but rather a form of niacin that takes longer to metabolize in the system, and thus does not trigger such an intense histamine release. Inositol hexanicotinate takes nearly ten hours to reach full serum levels in the blood, and provides all of the benefits of traditional niacin.