To    :  Natalie
Re    :  Pyridoxine (B6) and reduced milk production.


First, pyridoxine is rapidly phosphorylated to pyridoxine phosphate by liver
and various other tissues, so that circulating B6 is almost always
phosphorylated. I do not know for certain, but imagine that the effect on
prolactin is probably associated with the phosphorlated version.

B6 is stored in the liver and fetus.  Fetal levels are approximately 5 times
that of the maternal plasma. A well known fetal dependency syndrome has been
described, with full blown seizures following delivery,  where the infant
became dependent on high doses in utero, and then upon delivery (and limited
B6), begins to convulse.  Doses during pregnancy should be low, generally less
than 10 mg/day.

In your patient it is difficult to know for certain what the problem really is.
It is possible that 50 mg/day doses could reduce lactation in this patient, but
who is to know.  The only way to really determine this is to withdraw the B6
and see if the milk supply returns.

The effect of B6 on reducing carpotunnel pain is unusual to say the least.  I
concur with your suggestion, that she seek competent medical attention for the
carpotunnel syndrome,  since surgery works wonders on this problem.

Regards

Tom Hale