Propranolol, a beta-blocker that cuts heart rate, could silence the disastrous events on repeat in the minds of millions of people with PTSD.
The boom of the plane hitting the towers, the gray pieces floating in the air, and the people jumping out were parts of the scene replayed in physician Margaret Dessau's mind for years after the 9/11 disaster. She remembers looking out her apartment window to see a "guy with this white towel, and he's waving it." After he jumps, she hears children scream from a nearby school.
Nearly 10 years later, she described these memories as part of her post-traumatic stress disorder, or PTSD, to writer Anemona Hartacollis for the New York Times. Many PTSD sufferers replay disastrous events as memories that intrude on everyday life -- intrusive memories -- or in nightmares. They complain of not sleeping or concentrating. They may overreact to loud noises, become excessively alert and hypervigilant, and avoid reminders of the disaster. Dessau, who witnessed the attacks from her window, avoids looking at the skyline.
Intrusive memories are only part of a larger picture that often includes a sense of isolation, hopelessness, anger, and emotional numbness.
These symptoms have made the news for years, but less is known about effective treatment. If disturbing memories can be calmed by drug-enhanced treatment, millions of people who suffer from PTSD might benefit. This affects millions of adults in the U.S., including 9/11 survivors and combat veterans. Now Dr. Alain Brunet, a clinical psychologist at McGill University in Montreal, and his collaborators are halfway through a clinical trial to see if propranolol, a beta-blocker that reduces heart rate and blood pressure -- and has been proven to calm musicians facing stage fright -- can also reduce the strength of long-standing traumatic memories.
"I hear a woman scream ... there was a woman across the street from us, and we thought she had dynamite and was going to kill us. So I killed her."
They are giving the drug just before having people describe their memories in several sessions. Adrenaline and its cousin noradrenaline, the same chemicals that trigger the fight-or-flight response, enhance the storage of fearful memories. Propranolol may block these actions on a cluster of nerve cells deep inside the brain.
Don't try this at home. Propranolol requires medical supervision to be used safely.
I spoke with Brunet about the state of research on propranolol-enhanced treatment. He and his colleagues administered propranolol 75 minutes before the reactivation of frightening memories in 40 patients. "It really did wonders," he told me. "After six sessions, 70 percent of patients no longer met the clinical criteria for PTSD." His recent study with Dr. Roger Pitman, a Harvard psychiatrist who directs the PTSD and Psychophysiology Laboratory at the Massachusetts General Hospital, and others appeared in the 2011 Journal of Clinical Psychopharmacology. Their patients were victims of trauma such as accidents, rape, and spousal abuse, and most had symptoms for years or decades. Symptom relief compared favorably to generally lengthier treatment with psychotherapy alone as reported in earlier studies.
Their current international study, funded by both Canadian and U.S. agencies, is designed to show whether this treatment works even when patients are randomly assigned to either propranolol or a placebo.
In an earlier placebo-controlled study, Pitman reported in Biological Psychiatry that patients treated with propranolol in the emergency room hours after a physical trauma, like an auto accident, were much less likely to show physical reactions to recalling their experience three months later. Here the treatment appeared to reduce the formation of new memories.
The PTSD burden on combat veterans is huge. One said that every night "I hear a woman scream ... there was a woman across the street from us, and we thought she had dynamite and was going to kill us. So I killed her," he told psychologist Paula J. Caplan for the Washington Post. It turned out that she did have dynamite and was planning to kill them. "But every night," he continued, "I hear her scream, because, well, I wasn't raised to kill."