Scientists at FDA, duke university and other centers found new evidence suggesting that drugs used against Parkinson's disease boosts the dopamine level in the patients' brain. While dopamine is associated with various addictive behaviors, researchers are still looking if it is capable of turning Parkinson's patients into obsessive pleasure seekers.

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.

Some patients are now actually suing the manufacturers of dopamine agonists on the grounds that the companies did not do enough to warn about such risks of gambling and sex mania. Read Wayne Kanuch's case at the Washington Post.