A medical chatbot funded by advertising is now part of many American doctors' working day, and the public record on how well it checks its own answers is thin. OpenEvidence, founded in Miami in 2022 by Daniel Nadler, said physicians sent it more than 42 million prompts last month while diagnosing and treating patients. That is the company's own figure, and the reporting gives no outside count or comparison with other clinical tools to put it in scale.
If you've seen a doctor lately, there's a fair chance the tool was in the room.
How it spread through hospitals
The company says growth came mostly by word of mouth. "We're the first viral consumer internet app in healthcare," Nadler told the Financial Times. The tool searches medical journals and clinical guidelines, and the company points to a deliberately narrow list of sources, including the New England Journal of Medicine and JAMA.
Some hospitals noticed. Paul Testa, chief health informatics officer at NYU Langone, said the system sought a formal tie-up after finding clinicians were already using it as an "independent resource". Mount Sinai and Memorial Sloan Kettering have built it into their electronic health records. UCSF resident Nina Singh called it "a really useful tool" for adding patient context and deciding faster.
Where the money comes from
OpenEvidence raised $250 million in September at a $15 billion valuation, which brings its haul to nearly $1 billion in 18 months from backers including Andreessen Horowitz, Blackstone, Thrive Capital and Sequoia. A person close to the company told the FT it booked $100 million in ad commitments at the end of 2025 and is on track for $400 million to $500 million in ad revenue by the end of 2026. The company hasn't confirmed those figures.
Accuracy and ad questions
The reporting says researchers worry about accuracy as doctors lean harder on a tool that shapes treatment, but it doesn't name them or point to a published study, so those concerns remain untested by peer review as far as the sources show. Critics also question whether an ad model justifies the valuation.
The ad model itself is thinly described. The reporting doesn't say where advertisements appear for a doctor, whether in the clinical answer, a sidebar or elsewhere, nor which products are advertised, nor how conflicts of interest are managed or ads kept apart from clinical answers. That gap is worth watching.
Growth has limits too. The company pulled out of the EU and UK earlier this year over the bloc's AI Act, closing off two big markets. OpenAI and Anthropic are also pushing into healthcare. Nadler says trials with researchers, aimed at cancer and rare diseases, start in the coming weeks, and the company plans to apply AI to drug discovery. Those are plans, not results.
Would you want to know if your doctor's AI tool is paid for by advertisers?
Sources
Reported by the WattsUpNext desk from the sources linked below. Spot an error? Tell us at corrections@wattsupnext.com.
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