I don't think it's actually a matter of time. More like a function of using
too much, too often, to increase Hemoglobin beyond 11g/dl (which I believe is
the new recommended cut-off).

The potential problem is likely associated with the over-driven bone marrow
producing overly large RBCs, which can aggravate existing circulatory issues
(as in coronary artery disease, which narrows blood vessels). Drive the
average size of the RBCs too high and - like too many cars and not enough
asphalt - there's a chance that a traffic jam will result. Bad juju.

I was on 60K IU of Epogen for 35 weeks. I never experienced any issues
(thankfully!) though it only pushed my HGB up to barely over 10g/dl over the
entire period. But those two points made a HUGE difference in my QOL, and I
was grateful for it. "Life" with Hemoglobin at 8g/dl is an oxymoron.

So, fwiw, it seems to me that administering physicians should pay more
attention to RBC Distribution Width (aka "RDW") if the patient has any history
of circulatory issues. An overly high RDW would be a red flag warning to
reduce the Epogen dosage in such cases. In other words, it's less about HGB,
more about "fat" RBCs...

Cheers

/greyhackles

I sorta remember reading something like that on a package of birth control
pills :-o