What You Can Do
Search by meaning, not just keywords
Full-text search with faceted filtering, fuzzy matching, autocomplete, and semantic similarity powered by OMOPHub’s neural embeddings. Find concepts even when the phrasing doesn’t match the canonical terminology.
Resolve FHIR codes to OMOP standard concepts
Send a FHIR system URI + code (or a full
CodeableConcept) and get back the OMOP standard concept, domain assignment, mapping type, and CDM target table - all in one API call. Handles Maps to traversal automatically.Map between vocabularies
Translate codes across SNOMED, ICD-10-CM, LOINC, RxNorm, HCPCS, NDC, and every other OMOP vocabulary. Single-code, batch (up to 100 per request), and
CodeableConcept variants with OHDSI vocabulary preference ranking.Traverse concept hierarchies
Walk ancestor / descendant trees, expand concept sets, and explore non-hierarchical relationships (
Has ingredient, RxNorm has dose form, etc.). Build phenotype definitions that catch all relevant codes, not just the ones you knew to look for.Serve a standards-compliant FHIR Terminology Service
$lookup, $validate-code, $translate, $expand, $subsumes, $find-matches, $closure, plus the OMOP-specific $diff for vocabulary-release comparison. R4, R4B, R5, and R6 on the same endpoint. Plugs into HAPI FHIR, EHRbase, and any FHIR-aware client.Power AI agents with medical vocabularies
MCP Server exposes 11 tools to Claude, Cursor, VS Code, and any MCP-compatible client. Eliminate hallucinated codes by grounding LLM outputs against the OMOP source of truth - multilingual queries are accepted and translated on the agent side.
Who Uses OMOPHub
- ETL developers mapping source data into OMOP CDM tables
- FHIR integrators resolving clinical codes to standard OMOP concepts at the point of care
- Researchers building phenotype definitions and concept sets
- Pharma RWE / HEOR teams validating vocabulary coverage across studies
- AI / LLM builders grounding clinical AI pipelines against real terminology
- openEHR / EHRbase teams validating archetype terminology bindings against live vocabularies
Choose Your Starting Point
Quick Start
Get your API key and make your first request in 5 minutes.
FHIR Integration
The complete FHIR story - FHIR Resolver for ETL, FHIR R4/R5/R6 Terminology Service for clients, and when to use which.
FHIR Terminology Service
Spec-conformant
$lookup, $translate, $validate-code, $expand, $subsumes and OMOP-specific operations.AI & MCP Server
Connect Claude, Cursor, VS Code, or any MCP client to medical vocabularies.
EHRbase / openEHR
Validate openEHR template terminology bindings against OMOP vocabularies via FHIR.
HAPI FHIR
Point a HAPI FHIR server at OMOPHub as a remote terminology backend.
Python SDK
pip install omophub - search, map, resolve, and traverse from Python.R SDK
install.packages("omophub") - R6 client for vocabulary access in R workflows.Quick Example
One API call per common pattern:FHIR Resolve call is the single-API-call workflow no other terminology server offers: source code in, OMOP standard concept + CDM target table out, with Maps to traversal and semantic fallback handled server-side. See the FHIR Integration guide for the full response shape and batch variants.
Platform at a Glance
| Concepts | 11M+ standardized OMOP concepts |
| Vocabularies | 100+ including SNOMED CT, ICD-10, LOINC, RxNorm, NDC, HCPCS, ATC |
| FHIR system URIs | 20 canonical vocabulary URIs + OMOP unified omnibus |
| FHIR operations | $lookup, $validate-code, $translate, $expand, $subsumes, $find-matches, $closure, $diff |
| FHIR wire versions | R4, R4B, R5, R6 on the same endpoint |
| Search | Full-text, faceted, fuzzy, autocomplete, semantic |
| SDKs | Python (PyPI), R (CRAN), MCP Server (npm) |
| MCP tools | 11 tools for AI agent integration |
| Response time | Sub-50ms typical |
| Vocabulary updates | Synced with OHDSI ATHENA releases |
Need Help?
API Reference
Full endpoint documentation with request / response examples.
Status
API uptime and performance.
Dashboard
Manage API keys, usage, billing, and enterprise plans.
GitHub
Source for the SDKs, MCP Server, and reference implementations.