A Parkinson's drug was found to trigger behaviors such as pathological gambling, compulsive shopping and hypersexuality.

The side effects were seen in patients taking dopamine receptor agonist drugs, which activate the dopamine receptors and were prescribed to 2.1 million outpatients in the fourth quarter of 2012, The JAMA Network Journals reported

Over the course of a 10-year period there were 1,580 adverse drug events reported in the United States and 21 other countries that included the compulsive behaviors. Overall, there were: 628 cases of pathological gambling, 465 cases of hypersexuality and 202 cases of compulsive shopping. The total number of cases linked to dopamine receptor agonist drugs (also prescribed for restless leg syndrome and hyperprolactinemia) was 710.

To make their findings the researchers looked at adverse drug event reports for six dopamine receptor agonist drugs prescribed in the U.S. The team pinpointed these events in the 2003 to 2012 U.S. Food and Drug Administration's Adverse Event Reporting System database.

The 710 reports associated with dopamine receptor agonist drugs occurred primarily in patients with a median age of 55 years, 65.8 percent were male.

"Our findings confirm and extend the evidence that dopamine receptor agonist drugs are associated with serious impulse control disorders; the associations were significant, the magnitude of the effects was large and the effects were seen for all six dopamine receptor agonist drugs," the researchers wrote.

"At present, none of the dopamine receptor agonist drugs approved by the FDA have boxed warnings about the potential for the development of severe impulse control disorders as part of their prescribing information. Our data, and data from prior studies, show the need for these prominent warnings," they concluded.

The findings were published Oct. 20 in the journal JAMA Intern Med.