For those who plan to take high-dose niacin, the best advice appears to be to start a very low dose, e.g. 25 mg/d. This may cause a skin flush (30-60 minutes of warm skin) at first, but over several days the body gradually adapts to this dose and does not cause the skin flush. Then, slowly increase the dose over several weeks, taking the niacin in divided doses throughout the day, building up to 500 mg/d and over several months up to 1000 mg/d or higher, in consultation with your physician. You can start by breaking up 100 mg tablets into 4 pieces, taking one 25 mg piece per day at first, then after a few days increasing to 2 per day, and later up to 4 of the 25 mg pieces per day, one before each snack or meal. Once the body adapts to this dose, you may increase to one or more 100 mg tablets per day, and so on. [7] If at very high doses (1000 mg/day or higher) you note changes in your vision, especially in the central region (the fovea and macula) that you use to read fine print, you may want to lower the daily niacin dose by 50% or more to 1000 mg/day or below in divided doses. The vision problems may then disappear after a few weeks. This threshold effect has been reported by ophthalmologists who have studied the condition. [6] Of course, with any regimen of high-dose niacin, you should consult and work with your own physician.

Understanding Niacin Side Effects

Orthomolecular Medicine News Service

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