Niacin, Niacinamide, and Nicotinamide

My hubby was just prescribed Niacin to lower his cholesterol, and it got me thinking. Niacinamide is bad for those of us with GS, but Niacin (as vitamin B3) is fine. I always look when I read labels to make sure that if something has Niacin, that it is B3 as opposed to Niacinamide. Confused yet? I am. What the hell is the difference between the two?

Well, there are two types of niacin, or vitamin B-3. These are niacinamide, also called nicotinamide, and nicotinic acid. You also get some niacin when you consume foods containing tryptophan, since your body converts tryptophan to niacin. Sources of niacin include eggs, fish, meat, milk, yeast, grains and green leafy vegetables. Although you need some niacin to stay healthy, too much niacin can cause toxicity symptoms. Niacinamide side effects may include dizziness, stomach upset, nausea, gas, jaundice, vomiting, mouth pain, gout, irregular heartbeat, vision loss, ulcers, liver toxicity and a decrease in insulin sensitivity, especially at doses above 2 to 3 g per day.

I'm still confused, but figure if I just stay away from Niacinamide, I'll be fine :)