Super-Sensitive Nerves Play Key Role in Migraine Pain
April 27, 2000 -- Attention migraine sufferers: those weird pains aren't all
in your head. A new study shows that when people say headaches makes their hair
hurt, it's true.
In fact, the painful sensitivity to even the slightest touch -- experienced
by many or perhaps most migraine sufferers -- has led researchers to the
discovery of how migraines happen. It also offers clues to how they might be
stopped. That's according to a study in the journal Annals of
"The most interesting part of the study was when I asked patients 'Does
your hair hurt? Do you feel pain from your earrings or glasses or water in the
shower; can you shave without pain?'" lead investigator Rami Burstein, PhD,
tells WebMD. "In general, they didn't want to admit it because they thought
it had nothing to do with their migraines. After testing in the clinic showed
it to be real, I was able to say, 'This doesn't mean you are crazy -- just tell
me what you are feeling.' Then they went on and on and on about these symptoms
that they were reluctant to tell about."
Burstein and colleagues at Harvard University found that almost 80% of 42
migraine patients they studied experienced painful sensitivity to touch and/or
temperature in specific areas of their skin. This and earlier evidence from
laboratory animals led them to the conclusion that migraine pain results from a
chain reaction along the pain pathways leading to a region of the spine at the
base of the neck.
Chemicals released by pain receptors, the part of the nervous system that
senses pain, turn on nerve cells in the spinal cord. When these nerve cells get
stuck in the "on" position, they turn even the slightest sensation into
excruciating pain. This is why people with migraines say their head throbs --
the nerves connecting to their head become so sensitive that even the pulse of
blood in the brain is a source of pain.
This new understanding of how migraines happen explains why, for many
people, migraine medicine doesn't work once the headache has become severe.
"Not all patients experience increases in skin sensitivity -- and for
them existing pain medications are almost 100% effective at any point of the
migraine," notes Burstein, vice chair of the anesthesia department at Beth
Israel Deaconess Medical Center in Boston. "However, 79% of the patients in
our study exhibited this skin sensitivity. These patients will benefit from
currently available drugs only if they take them in the first hour after the
onset of an attack. If they take them later it is much, much less effective
because these drugs do not address the sensitization that develops in the
However, drugs that can prevent or reverse the chemical changes in the
spinal cord would benefit these patients. "There are hundreds of ways to do
that, and this is the kind of medicine that will eventually do the job,"
Burstein says. He and his Harvard University research team currently are
looking for drugs that can do this without too many unwanted side effects.