Dopamine receptor agonists are suspected to have caused serious impulse control disorders in at least 710 cases reported to the Food and Drug Administration’s adverse drug events database during a 10-year period.
The drugs, which are often prescribed for Parkinson’s disease, restless legs syndrome, and hyperprolactinemia, were implicated in more than 1,000 separate adverse events that included pathological gambling, hypersexuality, compulsive shopping, poriomania (wandering away from home), binge eating, kleptomania, and compulsive sexual behavior. Although this retrospective disproportionality analysis of information in a public database could not prove causality, “the associations were significant, the magnitude of the effects was large, and the effects were seen for all 6 dopamine agonist drugs” available in the United States, reported Thomas J. Moore of the Institute for Safe Medication Practices, Alexandria, Va., and his associates (JAMA Int. Med. 2014 Oct. 20 [doi: 10.1001/jamainternmed.2014.5262]).
These findings confirm and extend those of several previous reports in the literature, but none of the dopamine receptor agonists – pramipexole, ropinirole, cabergoline, bromocriptine, rotigotine, and apomorphine – currently carry a boxed warning about the potential for developing severe impulse control disorders. These behaviors can have catastrophic effects on jobs, marriages, and family finances. “Physicians who prescribe dopamine agonists should vigilantly monitor their patients, and ensure that patients, families, and caregivers are counseled about [this] risk,” the investigators wrote.
Noting that these six agents accounted for 2.1 million dispensed outpatient prescriptions during a single quarter of 2012 in the United States alone, the researchers examined a Food and Drug Administration (FDA) database of all domestic and foreign reports of serious drug events during 2003-2012. They focused on 1,580 reports of serious impulse control disorders and excluded cases involved in litigation or clinical studies. A total of 710 cases were related to dopamine receptor agonists, of which 48% were reported from foreign countries, said Mr. Moore, who is also with the department of epidemiology and biostatistics, George Washington University, Washington, and his colleagues.
The investigators calculated the proportional reporting ratio, “a ratio similar in concept to the relative risk ratio,” between these cases and each individual dopamine receptor agonist. They found that the proportional reporting ratio of each drug was high and statistically significant. In addition, the number of case reports rose steadily over time, from both within and outside the United States.
“Our data, and data from prior studies, show the need for these prominent [boxed] warnings” in the prescribing information for these drugs, the investigators said.
Mr. Moore and one of his associates reported serving as consultants or expert witnesses in civil and criminal litigation involving many psychiatric drugs, not including the six dopamine receptor agonists in this study.