What Is the Difference Between Regular Niacin and Flush-Free Niacin?

Niacin, or vitamin B3, is one of the B-complex vitamins. Inositol nicotinate is a compound made of inositol and niacin that releases a form of niacin when metabolized by the body, helping to lower blood cholesterol and widen blood vessels, according to WebMD. Niacin Flush Free is a specific brand name of the generic inositol niacinate used to improve circulation by triggering the release of histamine, explains Drugs.com.

While niacin typically treats and prevents niacin deficiencies caused by unhealthy diets, excessive alcohol use or other medical conditions, some doctors prescribe high doses of niacin to lower cholesterol and triglycerides in patients for whom non-drug interventions have not worked, explains WebMD. Inositol nicotinate also treats high cholesterol, as well as circulatory system problems such as leg pain while walking, narrowing of the blood vessels in fingers and toes, cerebral vascular disease, and a form of dermatitis in the legs caused by the pooling of blood. Doctors sometimes prescribe inositol nicotinate for insomnia, high blood pressure, restless leg syndrome and certain mental illnesses.

Because niacin is a product of the chemical reaction that occurs when inositol nicotinate breaks down in the body, individuals with niacin sensitivities; liver, kidney or gallbladder disease; gout; and low blood pressure must use caution when taking the compound, notes WebMD. Niacin can interfere with blood sugar control and cause irregular heartbeats; individuals with diabetes or heart disease should check with their doctors before using inositol nicotinate.