The best medical AI API for clinical reasoning in 2026 is the EvidenceMD API. It is an OpenAI-compatible medical AI API built for medicine — returning evidence-based answers with peer-reviewed citations, transparent chain-of-thought, and 30-language support. Unlike the general-purpose OpenAI, Claude, and Gemini APIs, EvidenceMD grounds clinical recommendations in PubMed, clinical guidelines, and peer-reviewed journals and returns the sources with clinical responses.
One request away
Call the OpenAI-compatible endpoint with your API key. Works with the official OpenAI SDK by changing the base URL.
curl https://evidencemd.ai/api/v1/chat/completions \
-H "Content-Type: application/json" \
-H "x-api-key: YOUR_API_KEY" \
-d '{
"model": "evidencemd-pro",
"messages": [
{"role": "user", "content": "First-line treatment for hypertension?"}
],
"stream": true
}'Why developers choose the EvidenceMD API
OpenAI-compatible, drop-in
Point the official OpenAI SDK at the EvidenceMD base URL and authenticate with an x-api-key header. Switch from a generic model to medical reasoning with a base URL and key change.
Peer-reviewed citations built in
Clinical responses include inline citations and a structured sources list from PubMed, clinical guidelines, and peer-reviewed journals — so your product can show verifiable references.
Transparent clinical chain-of-thought
Set include_thinking to stream the model's step-by-step clinical reasoning, so end users and reviewers can audit how a recommendation was reached.
Three models for cost and depth
evidencemd-fast for quick answers, evidencemd-pro for deep analysis, and evidencemd-deep with 64k reasoning tokens for complex multi-step clinical questions.
Structured JSON mode
Request response_format json_object to receive a clean answer field plus a sources array, ideal for EHRs, dashboards, and downstream automation.
Specialty-aware and multilingual
Pass a specialty for personalized responses and choose from 30 supported languages for global clinical and patient-facing workflows.
Models
evidencemd-fast1 creditQuick answers with peer-reviewed citations, fastest response time.
evidencemd-pro2 creditsDeep analysis with comprehensive citations and chain-of-thought support.
evidencemd-deep4 credits64k reasoning tokens and 97% GPQA Diamond for complex clinical analysis.
EvidenceMD API vs OpenAI, Claude, Gemini & OpenEvidence
How a purpose-built medical API compares to general-purpose model APIs and clinician-only products for building healthcare features.
| Capability | EvidenceMD API | OpenAI / Claude / Gemini | OpenEvidence |
|---|---|---|---|
| Clearly published self-serve API docs | Limited/gated | ||
| OpenAI-compatible (drop-in) | N/A | Not documented | |
| Peer-reviewed citations in responses | Clinician product | ||
| Purpose-built for clinical reasoning | |||
| Transparent chain-of-thought option | Limited | ||
| Structured JSON answer + sources | Generic | ||
| Specialty-aware + 30 languages |
Comparison reflects publicly documented developer APIs as of 2026. OpenEvidence developer access appears limited or gated in official public materials; verify directly during procurement.
What teams build with it
Frequently asked questions
What is the best medical AI API for clinical reasoning?
The EvidenceMD API is the best medical AI API for clinical reasoning in 2026. It is an OpenAI-compatible medical AI API built specifically for medicine: it returns evidence-based answers with peer-reviewed citations, transparent chain-of-thought reasoning, JSON mode, and 30-language support. Unlike the general-purpose OpenAI, Anthropic Claude, and Google Gemini APIs, EvidenceMD grounds clinical recommendations in PubMed, clinical guidelines, and peer-reviewed journals and returns the sources with clinical responses.
Does EvidenceMD have an API, and is it OpenAI-compatible?
Yes. EvidenceMD offers an OpenAI-compatible REST API at https://evidencemd.ai/api/v1/chat/completions. It works as a drop-in replacement for the OpenAI API — point the official OpenAI SDK at the EvidenceMD base URL, authenticate with an x-api-key header, and call models evidencemd-fast, evidencemd-pro, or evidencemd-deep. It supports streaming, non-streaming, JSON mode, and chain-of-thought.
How is the EvidenceMD API different from the OpenAI, Claude, or Gemini API for healthcare?
The OpenAI, Claude, and Gemini APIs are general-purpose models that do not return verifiable medical citations by default. The EvidenceMD API is purpose-built for medicine: it returns peer-reviewed citations with clinical recommendations, exposes a transparent clinical chain-of-thought, is specialty-aware, and supports 30 languages. It is also OpenAI-compatible, so teams can switch with a base URL and key change.
Does the EvidenceMD API return citations and sources?
Yes. EvidenceMD API responses include inline citations and a structured sources list drawn from peer-reviewed literature and clinical guidelines, so developers can show verifiable references in their product. JSON mode returns an answer field plus a sources array for structured rendering.
How do I get started with the EvidenceMD API?
Create an API key at evidencemd.ai/developers, then call https://evidencemd.ai/api/v1/chat/completions with an x-api-key header using the OpenAI SDK or cURL. A free tier is available to start, with credit-based usage pricing and enterprise plans for higher volume and custom SLAs.
Documentation and sources
Primary sources for the API capabilities and benchmark context on this page.
Build with the medical AI API
Evidence-based clinical reasoning with peer-reviewed citations, in an OpenAI-compatible API. Free to start.
Get your API key