yikes . . .
My experience (and mine has never been that high) is that
it takes multiple donations bring about a significant,
meaningful drop in hematocrit.
Also, hydration, that is being well hydrated plays a huge part.
I do not think that there is hard and fast “rule” as to how
much it will drop with each donation. Like they say, your
mileage may vary. Just be consistent, keep well hydrated,
not just pre and post donation / blood test, but always.
I say blood test, because that is really where hydration can
make a difference in test results. (Hydration will also drop
the amount of time it takes to give a pint of blood. The
“record” I hear is ~ 3 minutes, and she was extremely well
hydrated. I take about ~9 minutes.)
Yours is very high and that is not a good sign. I would
definitely do something about, what I don’t know but
giving blood would not be a bad place to start. I wish
you all the best getting this under control.