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From literary success to financial ruin
Children's author Sally Gardner enjoyed sudden fame and wealth in her early 40s, with her debut book selling 2.5 million copies and earning prestigious awards like the Carnegie Medal. Yet her newfound success came with an unexpected struggle: compulsive spending that left her £500,000 in debt.
Gardner, now reflecting on the past two decades, describes a period of lavish purchases-including a £3,000 bathtub, artwork by pop artist Peter Blake, and frequent trips to Parisian boutiques. She hid her spending from friends, lying about new clothes and accumulating debts that forced her to sell her north London home and downsize.
"Suddenly, I am in a different place, and for the first time in my life, earning really well."
Sally Gardner
The hidden trigger: medication for restless legs
Gardner's compulsive behaviour coincided with her doctor prescribing dopamine agonist drugs for Restless Legs Syndrome (RLS), a condition she had endured for years. The medication provided immediate relief from her symptoms-an uncontrollable urge to move that disrupted her sleep and daily life-but came with an unanticipated side effect: impulsive spending.
"I had no idea what had happened to me," Gardner says. "It was like, 'Who are you? What are you doing?'" She recalls buying the same pair of shoes five times and ten dog beds for her Yorkshire Terrier, all while battling chronic sleeplessness and menopause.
A widespread but overlooked side effect
Gardner's experience is not isolated. Over the past 18 months, the BBC has gathered hundreds of accounts from patients and families describing the devastating impact of dopamine agonist drugs. These medications, prescribed for conditions like Parkinson's, RLS, and pituitary tumours, are known to trigger impulsive behaviours, including gambling, hypersexuality, and compulsive shopping.
Many patients reported accumulating massive debts, losing relationships, or even facing homelessness. One woman described filling entire rooms with unnecessary purchases, while others recounted criminal behaviour or suicidal thoughts. Women, in particular, felt their struggles were dismissed as mere extravagance rather than a medical issue.
Gender bias in diagnosis
Experts suggest that compulsive shopping, though as common as gambling or sexual compulsions, often goes unnoticed longer because it lacks the same social stigma. Valerie Voon, a neuropsychiatry professor at the University of Cambridge, explains that online shopping allows impulsive behaviour to continue unchecked, as there is no immediate feedback or negative consequences.
"When you're online shopping, you don't get feedback very quickly. You can just order multiple things online and not be that conscious of what you're doing."
Valerie Voon, University of Cambridge
Guidelines from the UK's National Institute for Health and Care Excellence (NICE) require doctors to discuss impulsive behaviour risks with Parkinson's patients, who are predominantly men. However, no such guidelines exist for RLS patients, who are mostly women. Gardner calls this disparity "another health scandal where women are sidelined."
Regulatory response and lingering risks
The UK's Medicines and Healthcare products Regulatory Agency (MHRA) is reviewing warnings about impulsive behaviour linked to dopamine agonists following the BBC's investigation. While manufacturers insist the drugs' benefits outweigh the risks and that warnings are clearly stated, patients like Gardner argue they were never adequately informed.
Gardner only connected her behaviour to the medication after her daughter shared a link to the BBC's Impulsive podcast series, released in February 2026. "How had I not joined anything together on this?" she recalls thinking. Since reducing her dosage, she battles daily urges to spend, questioning every purchase.
"It's there all the time, and I battle with it every day. With everything I buy, I have to think, 'Is this compulsive? Am I doing it again?'"
Sally Gardner
Seeking answers
The NHS advises patients taking dopamine agonists to consult their doctors if they have concerns. Gardner, however, remains on the medication because it is the only treatment that effectively manages her RLS symptoms. She expresses relief at finally understanding the cause of her behaviour but remains angry about the years lost to compulsive spending.
"I will live with the consequences of the spending for the rest of my life," she says.
