My experience is one of the practical application of the following
idea.
------------------------------------------------------------------------------------------------

Co-administration of equimolar doses of betaine may alleviate the
hepatotoxic
risk associated with niacin therapy.

McCarty MF.

Pantox Laboratories, San Diego, California 92109, USA.

High-dose niacin has versatile and substantial efficacy for the
treatment of
hyperlipidemias, but its utility is compromised by various side
effects, the most
serious of which is liver damage. It is proposed that this
hepatotoxicity
reflects the high demand for methyl groups imposed by niacin
catabolism, leading
to a reduction in hepatic levels of S-adenosylmethionine (SAM).
Depletion of the
hepatic SAM pool has likewise been shown to mediate, at least in part,
the
hepatotoxic effects of ethanol, methotrexate, and niacinamide. If
niacin does
indeed decrease SAM, a likely consequence would be a counterproductive
elevation
of plasma homocysteine. Conceivably, methyl group deficiency, by
altering
membrane properties of skeletal muscle, also contributes to niacin-
induced
insulin resistance. Concurrent betaine supplementation - preferably
administered
as a complex with equimolar amounts of niacin - may represent the most
cost-effective way to prevent niacin-mediated depletion of SAM and
thus avoid
hepatotoxicity (and possibly other adverse effects) while controlling
homocysteine. Betaine also merits evaluation as an adjuvant to
methotrexate and
niacinamide therapies.

PMID: 10985907 [PubMed - indexed for MEDLINE]