1. Warning Signs

2. Wonder drugs


3. Dopamine Hits


4. Big Pharma, Big Secret


5. Restless


6. Chasing Losses


16 February 2026


When Freddie's father Bill is detected with Parkinson's, his medication provides him a new lease of life. He begins ticking things off his retiree bucket list - taking a trip, sky diving, golf.


But then Freddie notices that his previously reasonable dad has actually started acting unusually.


BBC Investigations correspondent Noel Titheradge has actually spent more than a year speaking to individuals whose behaviour changed radically after taking a classification of prescription drugs called dopamine agonists.


These drugs enhance activity in the brain - they were recommended more than 1.5 million times in the UK last year to deal with Parkinson's illness and other movement conditions.


But they have well established side results - around 1 in 6 individuals who take them establish impulse control conditions, which can include hypersexuality, binge eating, compulsive gambling and shopping.


If these adverse effects have been learnt about for years, why weren't some clients and their families correctly alerted or kept an eye on?