OpenEvidence says many US physicians sent more than 42 million prompts to its medical search chatbot last month. The company claims usage by nearly two-thirds of the country’s doctors, a level of adoption that has helped it raise almost $1 billion in 18 months and reach a $15 billion valuation.
The service searches a focused collection of medical journals and clinical guidelines. Hospitals including Mount Sinai, Memorial Sloan Kettering and NYU Langone have integrated it with electronic health records, while physicians interviewed for the report said it can speed literature review and decision support.
Its business model relies on advertising. A source close to the company expects $400 million to $500 million in ad revenue by the end of 2026, raising questions about incentives in a tool used around patient care. OpenEvidence also withdrew from the EU and UK this year over the EU AI Act.
Evidence about quality is incomplete. A Mayo Clinic study found evidence-based recommendations in five sampled cases, while a Nature paper reported weaker clinical-benchmark performance than general models. Doctors remain responsible for treatment decisions, and researchers warn that junior clinicians may over-rely on tools before developing foundational knowledge.