Change the channel: The
future of pain relief
Until a cure comes along, better pain
medication is urgently needed. Researchers
are also looking to stop pain at its source.
Dr. Stephen Waxman and his colleagues at
Yale University and the VA Connecticut
center are targeting pain at the level of a
single atom. For decades, they have been
building a case for the central role of “sodium
ion” channels, tiny gateways that regulate
nerves by letting sodium flow in and out of
the cell, one charged atom (ion) at a time. If
for some reason they let in too many ions, it’s
as if lightning strikes the nervous system and
sparks the pain response.
Of the nine different ion channels for
sodium (Na, in chemical-ese), the Nav1.7 and
Nav1.8 channels are under closest scrutiny
for MS pain. Dr. Waxman’s lab and others are
aggressively studying whether blocking them
can actually stop—not blunt—nerve pain.
“Because we have a well-defined and
specific molecular target, answers should
come,” he said. “This has become a major effort
in the pharmaceutical and biotech sectors. It
will take some years, possibly five, possibly
ten or more, yet I am very hopeful.”
He also thinks it might be possible to
block needless chronic pain without blocking
functional pain, the useful kind that keeps us
out of trouble. “After all,” he said, “Many known
medications have a ‘therapeutic window,’ an
optimum dose at which disease symptoms are
reduced without unacceptable side effects.”
As always, the best hope for MS lies in early
intervention. “By preventing demyelination or
axonal damage, it may be possible to reduce
the likelihood of developing MS pain alto-
gether,” he concluded. —RA
CBT
“The randomness [of MS pain] is hard on people,” Dr. Edhe noted. “They never know what
they’re going to have to deal with day to day.”
The unpredictability and the fatigue from sleep
loss make other issues worse, including mood
disturbances, anxiety and social relationships.
Cognitive-behavioral therapy (CBT) can help.
CBT is a talk therapy that uses the mind’s
ability to change emotions and how symptoms
are perceived by challenging habitual thought
patterns and behaviors. It has been found to help
in many painful ailments. It might not make pain
go away, but it can foster behavior that minimizes
the impact.
For example, Dr. Ehde explained, thinking “oh
this is awful” or “I can’t stand this” are typical
responses to pain that actually make pain worse.
“People with MS can employ more helpful or
constructive thoughts instead, such as ‘I may be
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