Do dopaminergic drugs make obsessive pleasure seekers?
rescription For an Obsession? Gambling, Sex Manias Called Surprise Risks Of Parkinson's Drugs
By Shankar Vedantam
Washington Post Staff Writer
When Wayne Kanuch received a diagnosis of Parkinson's disease in 1993, the last thing he imagined was that the drug prescribed to treat his illness would turn him into a compulsive gambler and put his libido into overdrive.
Kanuch's marriage ended in divorce, partly as a result of the sexual pressures he placed on his wife, and he began losing fortunes at the racetrack. He was fired from his job at Chevron for trolling for dates on the Internet while at work, and he quickly went bankrupt.
"I contemplated suicide a couple of times," he said in an interview last week. "Everyone was blaming me, and I was looking at the mirror and blaming myself and asking why I could not stop."
New evidence unearthed by scientists at the Food and Drug Administration, Duke University and other centers suggest the reason Kanuch could not stop is that the drug being used to treat Parkinson's boosted the level of dopamine in his brain. Researchers are looking into the possibility that dopamine, which is associated with a host of addictive behaviors, may turn some Parkinson's patients into obsessive pleasure seekers.
Now, some patients are suing the manufacturers of these drugs to recover the money they lost gambling, on the grounds that the companies did not do enough to warn about these risks. Kanuch has not yet sued but plans to do so.
So far, there is no definitive evidence on the connection between dopamine enhancers, known as agonists, and compulsive gambling. The behavioral anomalies, though dramatic, are probably rare among the thousands of Parkinson's sufferers who take the drugs. There have been no controlled studies looking into the possible link.
Dopamine encourages activities with a payoff, and makes itself scarce when things go wrong. By taking more dopamine, you become blind to negative consequences, and are more goal driven. Hence the gambling and sex.