Nicotine May Help Brain Disease
WASHINGTON, Feb 22, 2000 (AP Online via COMTEX) -- The same nicotine
that makes cigarettes so addictive may also have a good side.
Researchers say it shows promise against Parkinson's disease and a
variety of other brain conditions.
In a variety of studies reviewed Monday, doctors said the evidence is
mounting that nicotine can relieve symptoms by changing the way brain
uses message-carrying chemicals called neurotransmitters.
Researchers are testing nicotine patches for neurological diseases in
both children and the elderly, and drug companies are competing to
develop nicotine substitutes that have fewer side effects.
At a conference Monday, doctors said the field's first gold-standard
study -- one in which dummy treatments are rigorously compared with the
real thing -- suggests the patch shows promise in children with
Tourette's syndrome, a strange affliction in which victims may have
violent urges and shout obscenities, and exhibit a spate of tics.
Still, nicotine has many drawbacks, including its unsavory reputation
as the addictive grabber in cigarettes. Some experts believe nicotine's
real future is in fake forms of the drug.
''The problem with nicotine is that it is nicotine. You're asking
parents to put their kids on nicotine,'' said Dr. Paul R. Sanberg of
the University of South Florida, who has tested the drug on more than
100 young Tourette's patients.
Typically, doctors treat Tourette's with Haldol, a powerful
tranquilizer that is also used against schizophrenia. In the latest
study, Sanberg and colleagues combined nicotine patches and Haldol in
70 children, half of whom got dummy patches.
The study found those on nicotine did better and were able to control
their symptoms with lower than usual doses of Haldol. ''The data
suggest that a low-dose nicotine patch may be useful in Tourette's
syndrome,'' said Sanberg.
He and others experimenting with nicotine described their research at a
conference sponsored by the American Association for the Advancement of
Science.
Nicotine patches and gum are available in drugstores without
prescriptions. They are intended to help smokers wean themselves off
cigarettes.
The researchers cautioned that smoking is a bad way to get medical
nicotine. Besides the obvious cancer risk, drug levels spike much
higher in cigarettes.
They also say more research is needed before nicotine patches become
routine to treat diseases. However, Sanberg said that if Tourette's
patients cannot control their symptoms with standard drugs, a low-dose
patch might be worth trying.
Nicotine has been tested for many years in small-scale experiments
against Alzheimer's disease and more recently against Parkinson's
disease. Parkinson's causes tremors, rigid limbs and a shuffling walk,
and like Alzheimer's, it may also result in problems with memory and
thinking.
Dr. Paul Newhouse of the University of Vermont tried nicotine patches
on 15 Parkinson's patients. Although there was no comparison group, his
pilot study suggested that nicotine substantially improved their
movement and relieved their mental difficulties.
Newhouse also tested a synthetic form of nicotine, Abbott Laboratories'
ABT-418, on six Alzheimer's patients. Despite its small size, Newhouse
said patients showed ''a significant improvement in verbal learning and
memory'' on standardized tests.
Since no drug firms have exclusive rights to nicotine, researchers say
companies have little interest in paying for studies to prove its
health benefits. However, several are working on nicotine substitutes
that can be patented. These drugs could be more precisely targeted
against specific disorders, carry fewer side effects and be available
as pills rather than patches.
Nicotine is thought to work by regulating the brain's levels of
message-carrying chemicals, such as dopamine and acetylcholine.
Researchers say they see no sign that patients get hooked on the patch.
The main side effects are nausea and itching around the patch.
Another drawback of the patch is the possibility it might trigger heart
attacks, as the much higher nicotine in cigarettes can. Sanberg said
that in his studies, children's heart rates rise about 10 percent, but
they show no other obvious heart effects.
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