The symptoms you describe are much more likely to be
mild decompression sickness (the bends) rather than
a problem with Oxygen or the lack of it. The text
book remedy is to go onto pure Oxygen about half an
hour before take-off to progressivly reduce the amount
of Nitrogen in the blood, but that is both impractical
and a bit OTT to get rid of a headache.

At 04:18 09 October 2005, wrote:
All,
I fly from an airfield that is over 6000 feet elevation,
therefore I
use oxygen on most flights. I have found that I get
a headache that
lasts for several hours following every flight. I
use an EDS system
and have tried several different settings; everything
from its maximum
setting which delivers oxygen when I'm sitting on the
ground, up to
having it begin to deliver oxygen starting at 10,000
feet. When we
first moved here, it took a day or two to acclimate
and the headache I
had then is the same as my post-flight symptoms as
far as I can tell.
Has anyone experienced similar symptoms? I feel fine
in the air and
immediately after the flight, but a half hour or so
later I get the
headach. The only thing I can figure is that my physiology
must be
sensitive to changes in oxygen levels. Any suggestions
on something I
may be doing wrong? Something I can do to prevent
my oxygen hangovers?
Thanks.