A year‑long BBC investigation has shed new light on known side effects of medications for Parkinson’s disease, including gambling and sex addictions, yet the European Medicines Agency says it will not revise its rules.
Parkinson’s medication belongs to a group of drugs called dopamine agonists, which are also prescribed for other conditions such as restless legs syndrome (RLS). They increase dopamine activity, and while this helps to regulate movement, it can also overstimulate motivation and the brain’s reward system, leading to the development of impulsive behaviours.
Over the last year, BBC investigations correspondent Noel Titheradge has collected stories from hundreds of patients, among them the example of a father whose impulsive behaviour linked to his treatment led him to embezzle £600,000 (€700,000) from his clients to pay for sex and antiques. The man later took his own life, as did his son.
One patient, Charleen, who lives in Massachusetts in the United States, was prescribed a dopamine-boosting drug for depression. While no side effects were noted in the first months – as was the case for other patients interviewed – she later developed an addiction to sex, as she describes in the BBC podcast “The Global Story”.
“I needed to have sex with as many people as I could,” she said. She also reported aggressive behaviour on the road and compulsive shopping in clothing stores “until there was no money left.” She eventually withdrew all her retirement savings and spent them entirely.
Change of leaflets
The companies manufacturing these drugs told the reporter that the side effects were stated, and the medicines continued to be approved. However, patients have argued that the side effects should be more clearly described, and instead of “hypersexuality”, leaflets should mention that the medication can cause severe porn addiction.
A study published in 2010 estimated that as many as one in six Parkinson’s patients taking these drugs experience impulse control disorders. However, for one of the drugs, the leaflets in the UK also described the side effects as “uncommon”. After being alerted by the BBC, the UK’s drug safety regulator said it would change the label to “common”.
Patients like former sex addict Charlene say they never linked their sudden change in behaviour to the medication and now share their stories to warn others. They say it is hard to prove that one was not properly informed.
Particularly, sex addiction is harder to document than gambling addiction, where a quick look at bank accounts can reveal a clear before-and-after difference. In both cases, the journalist notes, patients often feel too ashamed to discuss these issues with their doctors.
At the EU level, however, a reassessment is not currently planned, as it would require new evidence. Asked by Euractiv, the EMA said that “the product information for dopamine agonist medicines accurately reflects the current state of scientific knowledge.”
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Source:
www.euractiv.com