Parkinson's drug caused ‘deviant' sexual behaviour

Telegraph

11-03-2025

A popular drug prescribed for Parkinson's disease caused side effects of 'deviant' sexual behaviour and gambling addiction.
Patients prescribed the drug ropinirole for movement disorders, which includes Parkinson's and restless leg syndrome (RLS), have said they were not warned about serious side effects that led people to seek out high-risk behaviours.
A report by pharmaceutical firm GSK revealed it learned in 2003 of the link between the drugs and 'deviant behaviour', according to the BBC.
The GSK review cited two men taking the treatment for Parkinson's who were charged with sexual offences, including one for child sexual assault.
A further 20 women spoke out about their side effects after they were prescribed the drugs for RLS – a condition that causes an irresistible urge to move – as part of a BBC investigation.
Ropinirole, known by brand Requip, is a dopamine agonist – this class of drugs work by mimicking the behaviour of the chemical dopamine, which occurs naturally in the brain and helps regulate movement and mood.
Its levels increase when we experience pleasure or rewards, but agonist drugs can over-stimulate these feelings and under-stimulate the appreciation of consequences, leading to impulsive behaviour, according to academics.
While some women reported seeking out risky sexual behaviours, others said they felt compelled to gamble or shop and racked up debts of more than £150,000.
Triggered unprecedented sexual urges
A woman known as Claire revealed she first began taking the drug when she developed RLS during pregnancy, which led to a relentless need to move, sleeplessness and a crawling sensation under her skin.
She said she was not warned by doctors about the side effects and while ropinirole helped her symptoms, she began to feel unprecedented sexual urges after a year.
Claire told the BBC she began leaving her house in the early hours of the morning to cruise for sex. She would wear a see-through top and jacket, flash her chest at any man she could find, and did so regularly, in increasingly dangerous locations, despite having a partner.
'There remains an element in your head that knows what you're doing is wrong, but it affects you to the point that you don't know you're doing it,' she said.
It took her years to connect the urges with the medication and they disappeared almost immediately after she stopped taking the drugs.
She said she feels complete 'shame' and is 'mortified' at the danger she placed herself in.
Other women reported similar sexual and gambling addictions, but say they were not warned about the drugs and did not make the connection.
Prof Valerie Voon, a professor of neuropsychiatry at the University of Cambridge, said patients taking ropinirole should be specifically warned about the side effects, and screened by the NHS, because their impact can be 'devastating'.
'There's a lot of stigma and shame attached to it, and people don't realise that it's associated with medication,' she said.
Impulsive behaviours, including gambling and increased sex drive, are listed side effects in medicine leaflets for dopamine agonist drugs – and are thought to affect between six per cent to 17 per cent of RLS patients taking them, according to the regulator, the National Institute of Health and Care Excellence.
Jailed for 'uncontrolled exhibitionism'
The GSK report from 2003 reportedly described the 'deviant behaviour' of two men who were prescribed ropinirole for Parkinson's disease.
The documents revealed a 63-year-old man sexually assaulted a seven-year-old girl, leading to a custodial sentence. His libido had increased significantly from the start of his treatment with ropinirole and his 'libido problem subsequently resolved' after his dose was reduced.
In the second case, a 45-year-old man carried out 'uncontrolled acts of exhibitionism and indecent behaviour'. His sex drive was reported to have increased before being prescribed ropinirole but his urges 'intensified' after the treatment.
A class action was brought against GSK in 2011 by four sufferers of Parkinson's disease. This was settled and GSK denied liability.
A GSK spokesman said: 'Extensive clinical trials and more than 17 million patient treatments worldwide since 1996 have continued to show Requip to be an effective treatment for Parkinson's disease and Restless Legs Syndrome, with a well-characterised safety profile.
'As with all medicines, Requip has potential side effects and these are clearly stated in the prescribing information. Patients should only take Requip under the direction of a medical professional.'
A spokesman for the Medicines and Healthcare products Regulatory Agency said: 'The MHRA approved product information for ropinirole and pramipexole contains warnings about the risk of impulse control disorder which can involve impulses of a sexual nature.
'As impulses are variable and individualised, a specific reference to 'deviant' sexual behaviour is not included but as outlined in the full text of the warning, the warning highlights that the impulses experienced can include activities that may harm the patient or others.
'It is important to note that not all patients experience this type of side effect and it is important for healthcare professionals to explain the possible risk to patients.'