Prescription cascade study: 1 in 10 Canadian patients affected by drug side-effect chains

A BMJ study of 2.3 million Canadian residents finds that prescription cascades—where side effects of one drug are misdiagnosed as new conditions and treated with additional drugs—occur in roughly 10% of patients starting certain medications. The phenomenon is especially dangerous for the elderly, who face polypharmacy risks. This highlights a systemic patient-safety issue but does not change immediate market dynamics.