Sounds like the clinical trials programs we use to approve drugs may have room to improve.
He had diabetes, and he had signed up for a study to see if taking a "statin" – a kind of cholesterol-lowering drug – might help. So far, so normal.
But soon after he began the treatment, his wife began to notice a sinister transformation. A previously reasonable man, he became explosively angry and – out of nowhere – developed a tendency for road rage. During one memorable episode, he warned his family to keep away, lest he put them in hospital.
Out of fear of what might happen, Patient Five stopped driving. Even as a passenger, his outbursts often forced his wife to abandon their journeys and turn back. Afterwards, she'd leave him alone to watch TV and calm down. She became increasingly fearful for her own safety.
Then one day, Patient Five had an epiphany. "He was like, 'Wow, it really seems that these problems started when I enrolled in this study'," says Beatrice Golomb, who leads a research group at the University of California, San Diego.