August 7, 2006

Alzheimer’s drug combats nerve gas in guinea pigs

By Anthony J. Brown, MD

NEW YORK (Reuters Health) - Treatment with galantamine, a
drug used to treat Alzheimer's disease, in combination with
atropine, protects guinea pigs from lethal doses of the nerve
agents sarin and soman and the insecticide parathion, new
research shows.

The toxic effect of these "organophosphorus" compounds
derives from irreversible blockage of an enzyme critical to
nerve function. The end result can be seizures and cardiac

At present, atropine and other drugs are used to treat the
toxic effects of organophosphorus compounds. However, these
treatments have various limitations, including an inability to
fully protect the brain from damage.

Galantamine protects nerves from these chemicals by
temporarily blocking the same enzyme, lead author Dr. Edson X.
Albuquerque, from the University of Maryland School of
Medicine, told Reuters Health. Unlike some of the other
anti-nerve gas agents, "the drug can get into the brain and
protect against the damage there."

As reported in the Proceedings of the National Academy of
Sciences, the researchers tested the effects of galantamine in
guinea pigs exposed to lethal doses of sarin, soman, and
paraoxon, the biologically active form of parathion. Atropine
was given to counter the effects of these agents outside the

Galantamine plus atropine safely and effectively
counteracted the toxic effects of the organophosphorus
compounds. Moreover, galantamine was well tolerated at the
dosages needed to prevent death.

Albuquerque believes that galantamine would be a welcome
addition to the atropine and other agents carried by military
personnel to counteract nerve gas exposure. The drug could also
be of use, he added, to workers at risk for exposure to
organophosphorus insecticides.

SOURCE: Proceeding of the National Academy of Sciences,
August 7th early edition, 2006.