TUESDAY, Sept. 12 (HealthDay News) -- The Alzheimer's drug rivastigmine (Exelon) improved memory in traumatic brain injury patients with moderate to severe memory loss, a new study shows.

As reported in the Sept. 12 issue of the journal Neurology, the study of 134 patients at 19 centers across the United States found that severely impaired patients who took the drug for 12 weeks had significantly improved attention and verbal memory test scores compared to patients who took a placebo.

In one test, 30 percent of patients taking rivastigmine remembered five or more additional words, compared to 10 percent of patients taking the placebo. The researchers said that the drug is believed to enhance the function of the neurotransmitter acetylcholine, which is involved in memory and learning.

While the drug improved memory in patients with moderate to severe memory problems, it was less effective in patients with milder memory loss.

"The beneficial effect of rivastigmine may not become apparent unless there is significant depletion of cholinergic activity in relevant brain regions causing a more profound impairment in memory or attention," study lead author Dr. Jonathan M. Silver of the New York School of Medicine, said in a prepared statement.

"This is an area where more research will be required to confirm these findings and to better define who may have the best response with rivastigmine," he said.

Side effects among patients taking the drug included nausea, upper respiratory tract infection, headache, dizziness and vomiting.

About 1.5 million people suffer traumatic brain injury each year in the United States and about five million people in the U.S. are currently living with a disability related to traumatic brain injury.

More information

The U.S. National Institute of Neurological Disorders and Stroke has more about traumatic brain injury.

SOURCE: American Academy of Neurology, news release, Sept. 11, 2006

Last Updated: Sept. 12, 2006

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