On call; No-flush niacin.

Q. In your January 2007 article on cholesterol, you said that no-flush niacin does not lower cholesterol levels. But my problem is low HDL cholesterol. Will no-flush niacin help my HDL even if it won't lower my LDL cholesterol?

A. Niacin can be used for three purposes: to lower the LDL ("bad") cholesterol, to lower triglycerides, and to raise the HDL ("good") cholesterol. Because the statins and other prescription drugs that have such a good ability to lower the LDL have only a modest ability to boost the HDL, niacin can be particularly helpful for people with low HDL levels.

To have benefit, though, niacin has to be absorbed into the bloodstream. Nicotinic …