The drug, called memantine, helps people with Alzheimer's disease think more clearly by reducing overactivity in the brain. But it also eases impulsivity, a trait tied to rash decisions and impractical purchases.
"In a way, compulsive buying is similar to other addictions in that people are thinking about the immediacy of the reward without considering the consequences," said study author Dr. Jon Grant, a professor of psychiatry at the University of Minnesota in Minneapolis. "We asked: Could we use a medication to essentially enhance decision-making as a way to help them with their behavior?"
Grant and colleagues recruited eight compulsive buyers, all women, to take memantine for 10 weeks, and used cognitive tests and surveys to track impulsive thoughts and spending. In the end, they found significant reductions in both.
"People with compulsive spending don't think through the full range of consequences of their behavior, and that improved with this medication," said Grant.
The study, published in the May issue of Annals of Clinical Psychiatry, gives hope to an estimated 6 percent of Americans who struggle with the euphoric highs and guilt-ridden lows of compulsive buying.
"It can interfere with people's jobs, their marriages," said Grant, describing how compulsive buyers squander their savings and invent lies to explain their actions. "All of this leads to incredible personal distress. A person might feel depressed and even suicidal because they don't know how to control their behavior and feel bad about being dishonest."
Ronnie Haring, a 38-year-old mother of two from Reading, Pa., recently told ABC's "Nightline" how she shopped in secret and hid all her purchases from her husband.
"He'd say, 'Is that something new?' and I'm like, 'No, I've had this for a while,' so it wasn't a lie. It just wasn't the truth," she said.
Haring ran up $50,000 in credit card debt shopping for clothes, furniture and toys for her kids.
"It just feels so good inside," she told Nightline. "You're kind of floating as you're going through it and then, essentially, you just fall ... very hard. You get home and you're like, 'Why did I buy all this?' And then you feel guilty. And the way to make yourself feel better [is] more shopping. And the cycle continues."
It took a trip to jail for shoplifting for Haring realize how serious her compulsive shopping habit had become.
"It was kind of like, 'You've hit rock bottom now. There's nowhere to go,'" she said.
"When people get caught up in cycles of addiction, they often do things that would be contrary to their character," said Grant, adding that shoplifting is not an uncommon consequence of compulsive buying. "They're desperate, both to spend and buy more as well as to cover up the debt they have."
Despite being widely recognized as a disorder on par with alcoholism or gambling addiction, compulsive buying is not listed in the DSM-IV and there is no standard treatment.
"There is some evidence that cognitive behavioral therapy can benefit people with this problem," said Grant, describing the psychotherapeutic technique that aims to replace dysfunctional behaviors with healthier habits. "Antidepressants have also been tried but were largely unsuccessful. But this study represents at least a possible pharmacological approach."
Before memantine can be approved for the treatment of compulsive shopping, it has to be tested against a placebo in clinical trials, said Grant, adding that the drug is also being tested in other impulse disorders, including alcoholism and obsessive compulsive disorder.
"For any behavior that's fun and healthy for most people, there's a small percentage of people who can't control it.," he said. "Whether one tends to drink too much, wants to wash their hands too much or spends too much, the drug seems to be able to cut across several disorders and home in on a common underlying problem."