"We urge patients to talk to their doctor before deciding to stop or start taking any medicine," Rhyne said. "Anyone receiving treatment with dopamine agonists who notices unusual behaviours, such as new or increased gambling urges, increased sexual urges or other intense urges should talk to their doctor."
Although the package insert lists the possible side effects, doctors should make sure patients are aware of them before prescribing the drugs, according to Dr. Joseph Jankovic, professor of neurology and director of the Parkinson's Disease Center and Movement Disorders Clinic at Baylor College of Medicine.
"There's a trade-off between reduction of motor symptoms and the side effects, Jankovic said. "As long as it's discussed and patients and their family are aware, I think most patients will agree that the benefits outweigh the risks."
But if a patient does develop behavioral side effects, they usually have to stop taking the drug. There are other treatment options, such as L-Dopa and deep brain stimulation. But these have risks and side effects too.
As many as 1 million people in the United States have Parkinson's disease, and up to 60,000 new cases are diagnosed every year, according to the National Parkinson Foundation.
With medications like dopamine agonists, newly diagnosed patients can maintain relatively normal lives for 15 years or more, Standaert said. But ultimately, the disease still catches up with them.
"We want to find a way to diagnose Parkinson's disease earlier and find a treatment that actually stops the disease from progressing," Standaert said.
In the meantime, treating the symptoms with drugs like dopamine agonists can help people with Parkinson's disease maintain normal lives, Standaert said.
"These side effects are colorful and serious, but rare," Standaert said. "These are very useful medications. People shouldn't be frightened, they should just know about the risks."