Scientists test pill to fade memories of traumatic events

ASSOCIATED PRESS

Scientists have been testing a pill that, when given after a traumatic event like rape, may make the resulting memories less painful and intense.

Will it work? It is too soon to say. Still, it is not far-fetched to think that this drug someday might be passed out along with blankets and food at emergency shelters after disasters like the tsunami or Hurricane Katrina.

Psychiatrist Hilary Klein could have offered it to the man she treated at a St. Louis shelter over the Labor Day weekend. He had fled New Orleans and was so distraught over not knowing where his sisters were that others had to tell his story for him.

"This man could not even give his name, he was in such distress. All he could do was cry," she said.

Such people often develop post-traumatic stress disorder, or PTSD. Only 14 percent to 24 percent of trauma victims experience long-term PTSD, but sufferers have flashbacks and physical symptoms that make them feel as if they are reliving the trauma.

Scientists say it happens because the brain goes haywire during and right after a strongly emotional event, pouring out stress hormones that help store these memories in a different way than it normally ones.

Taking a drug to tamp down these chemicals might blunt memory formation and prevent PTSD, they theorize.

Some doctors have an even more ambitious goal: trying to cure PTSD. They are deliberately triggering old bad memories and then giving the pill to deep-six them.

The first study to test this approach on 19 longtime PTSD sufferers has provided encouraging results, Canadian and Harvard University researchers report.

"We figure we need to test about 10 more people until we've got solid evidence," said Alain Brunet, a psychologist at McGill University in Montreal who is leading the study.

Memories, painful or sweet, don't form instantly after an event but congeal over time.

Propranolol can blunt this. It is in a class of drugs called beta blockers and is the one most able to cross the blood-brain barrier and get to where stress hormones are wreaking havoc. It already is widely used to treat high blood pressure and is being tested for stage fright.

Dr. Roger Pitman, a Harvard University psychiatrist, did a pilot study to see whether it could prevent symptoms of PTSD. He gave 10 days of either the drug or dummy pills to accident and rape victims who came to the Massachusetts General Hospital emergency room.

The eight who had taken propranolol had fewer stress symptoms than the 14 who received placebos, but the differences in the frequency of symptoms were so small they might have occurred by chance -- a problem with such tiny experiments.

Meanwhile, another study on assault and accident victims in France confirmed that propranolol might prevent PTSD symptoms.

One of those researchers, Mr. Brunet, now has teamed with Dr. Pitman on the boldest experiment yet -- trying to cure longtime PTSD sufferers.