Caroline Merin

Proud to launch @Leona_health today to scale human connection in healthcare. We have assembled the best team I've ever worked with to achieve our vision! Join us leona.health/en/careers

Gracias a @robertoah, @Jdsago y @eresinaeresina por sentarse conmigo y contarle a México lo que estamos construyendo con Leona!

Read more about our vision at @Leona_health here: milenio.com/opinion/varios…

In many parts of the world, WhatsApp is the core operating layer for daily life, where families communicate, businesses run, and increasingly, healthcare is delivered. But WhatsApp wasn’t built for healthcare, and physicians can lose hours navigating disorganized threads. Leona is building the fix: an AI-native operating system for providers, built directly into WhatsApp to bring clarity and clinical structure to patient communication. Since launching its Latin America beta in April, they have expanded organically to thousands of physicians, processing millions of patient interactions across more than a dozen countries. We’re leading Leona’s $14M seed round to build the world’s first AI copilot for doctors. Cofounders @merinsay, Tom Chokel, and Arela Solis bring deep operational and technical expertise, and we’re proud to partner with the team as they redefine how care is delivered across Latin America and beyond.

.@Leona_health is transforming WhatsApp into a healthcare OS for the world, giving doctors a mobile AI co-pilot to help them run their practice from anywhere. As a founder, Caroline brings rare product depth and a hopeful, ambitious view of the future of care. Excited for all that's ahead for this team. techcrunch.com/2025/12/16/ube…

The founder journey is better with friends like @celinehalioua—more fun, less lonely, and a daily reminder to raise the bar on what’s possible.

It was wonderful to chat with @MTemkin at @TechCrunch on our vision for Leona – the first mobile-first operating system for healthcare, powered through WhatsApp. While we're just getting started, we're proud to already be saving doctors 2-3 hours a day across 14 countries.

Kudos to @merinsay and the @Leona_health team on their launch announcement and seed raise from @a16z, @generalcatalyst, and @Accel . We invested at the pre-seed and are proud to have watched Caroline and team tackle one of healthcare’s most overlooked truths: doctors and patients already live on mobile, yet healthcare systems still don’t. Building an AI co-pilot for doctors that works natively inside WhatsApp is both deeply pragmatic and genuinely ambitious, especially starting in Latin America and building for the world. This is a rare combination of consumer intuition, operational empathy for doctors, and timing with AI that feels exactly right. Excited to see Leona scale human connection in healthcare, not replace it.

@julesyoo and @JayRughani immediately understood the immense opportunity that lies in building a new operating system for care that meets doctors and patients where they already are. We are honored to have @a16z and the best possible partners & healthcare investors lead our Seed

Having @amitku and @Accel in my court since day one has been one of the greatest joys of the founder journey thus far. It is rare to find people who believe in you before you even have a well formulated idea.

New @a16z investment: Most of us think of WhatsApp as a simple messaging app, but in many parts of the world, it also functions as the operating layer of daily life. It’s where families communicate, where businesses run, and increasingly, where healthcare is delivered. In LatAm, more than 85 percent of physicians rely on WhatsApp to schedule appointments, share results, and manage follow-ups. But WhatsApp wasn’t built for healthcare. Effective clinical communication requires structured workflows, clear accountability, and reliable tracking of patient needs. Instead, physicians are left navigating dozens of disorganized messaging threads with patients and families, with no visibility into urgency, patient status, and relevant clinical history. The result: hours each day consumed by manual sorting – time that should go towards patient care, not inbox management. The system needs a better answer, and Leona is building it. Leona is an AI-native operating system for providers, built directly into the channel physicians already rely on most: WhatsApp. Through direct integration with the messaging app platform, Leona brings clarity and clinical structure to patient communication – organizing messages, flagging urgency, and connecting each exchange to a longitudinal patient record. This co-pilot for clinical messaging is part of a comprehensive practice management platform that facilitates scheduling, documentation, and billing. The physician adoption is striking: since launching its Latin America beta in April, Leona has expanded organically to thousands of physicians, processing millions of patient interactions across more than a dozen countries, and saving providers up to three hours per day. As care increasingly lives in messages and mobile moments – delivered virtually, asynchronously, and beyond the four walls of the clinic – the need for infrastructure that can coordinate clinical workflows becomes increasingly urgent. Leona is building that backbone. Co-founders Caroline Merin (@merinsay), Tom Chokel, & Arela Solis bring deep operational and technical expertise to one of the region’s most urgent infrastructure challenges. We @a16z are proud to lead Leona Health's seed financing as they redefine how care is delivered across Latin America and beyond. @a16zBioHealth @julesyoo @generalcatalyst @hollsmaloney @marcbhargava @Accel @amitku @homebrew @satyap @hunterwalk @_KateRyder @velez_david

It was fun to share more about what we’re building at @Leona_health with @pimepardo & @federicoantoni 🦁🚀!

Excited to be an early user and investor in the @TryCoveAI team! Having seen @thestephenchau and @andyszy ’s talent first hand at UberEats, I’m confident there’s no better team to help us rethink and redesign how we can get the most out of AI

Two papers on the value of mixed gender teams for innovation: 🥼Analysis of 6 million medical papers shows mixed gender teams do more impactful & cited work 📈Randomized teams with different gender breakdowns ran a startup for a year. Teams close to 50/50 male-female did best.

Proud to be a ⁦⁦@Wharton⁩ alum 🙌🏻 wsj.com/articles/whart…

based on yc demo day, the two companies in the world producing the most founders in the world aren't google and facebook they're rappi and OYO

Ya llega #RappiCard a Mexico, la tarjeta de crédito #ComoDebeSer ! Sin anualidad y hasta con 3% de Cashback en tus compras de contado o a meses sin intereses. Únete a la lista de espera @rappipaymx rappicard.mx/?kid=1DG0V1

While I may be the first woman in this office, I will not be the last—because every little girl watching tonight sees that this is a country of possibilities.

The world needs more Martys! ♥️ May Every Woman Find Her Marty Ginsburg vogue.com/article/may-ev… via @voguemagazine

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