A recent study in the journal Neurology reports that impulse control disorders (ICDs) — compulsive gambling, shopping or eating, or excessive interest in sexual activity — are common in people with Parkinson’s disease (PD) who take medications called dopamine agonists. These drugs include Mirapex (pramipexole), Requip (ropinirole) and Neupro (rotigotine). While researchers have long recognized the association between ICDs and dopamine agonists, new data raises concern the risk may be higher than previously reported. These results could bring increased awareness of this drug side effect, which may help patients and their doctors better recognize and treat ICDs.
A French research team gathered information from 411 people diagnosed with Parkinson’s within the past five years. In the five-year study, 199 reported having an ICD. For those who’d taken a dopamine agonist, the ICD risk was 52 percent; for those who’d never been exposed to a dopamine agonist, the risk was 12 percent.
The researchers found an increased risk of ICDs with taking higher doses of dopamine agonists for longer periods as well as taking the dopamine agonists Mirapex (pramipexole) and Requip (ropinirole). They did note, however, that their study population was slightly younger, which may have led to an overestimation of risk. (Younger age increases the risk of impulse control disorders.)
These results should raise appreciation for ICDs and fuel conversations among patients, families and doctors. At every appointment and especially when starting or increasing dosages of dopamine agonists, doctors should talk about symptoms of ICDs and risks for developing an impulse control disorder (history of mood changes or addictive behaviours, for example). That way, patients and families can watch for and discuss the earliest signs of behavioural changes.
While many aspects of ICDs may be difficult to bring up with a loved one or your doctor, there should not be shame or embarrassment in these symptoms. They are true side effects of drugs that often resolve with a medication adjustment.
Like all drugs, dopamine agonists have potential benefits and risks. These drugs are beneficial for treating motor symptoms in many people with Parkinson’s. Impulse control disorders are a potential risk, but they don’t occur in everyone, and there are steps you, your doctor and family can take to monitor and adjust for these symptoms. If you’re taking a dopamine agonist, talk to your doctor before making any changes or stopping medication.