hhaau3platform
ProductsPricingDocs
Sign inGet started
All products
Available

Terminology API

A FHIR terminology service, hosted.

GETapi.haau3.com/v1/fhir/r4/CodeSystem/$lookup
Get started free
api.haau3.com

Request

GET /v1/fhir/r4/CodeSystem/$lookup
  ?system=http://loinc.org
  &code=<loinc-code>

Response

{
  "resourceType": "Parameters",
  "parameter": [
    { "name": "name", "valueString": "LOINC" },
    { "name": "display",
      "valueString": "<concept display>" }
  ]
}

What it does

  • Look up codes, expand value sets, validate codes
  • Standard FHIR responses, passed through verbatim
  • FHIR $lookup, $expand, and $validate-code

Built on

FHIR R4FHIR Terminology Service

Look up codes, expand value sets, and validate codes against standard code systems (LOINC today) through a standards-based FHIR terminology service, so you don't have to host one yourself. More code systems and operations are coming.

Start building today

Detailed developer docs live at docs.haau3.com.

Get started free
hhaau3platform

APIs for the healthcare ecosystem.

© 2026 haau3. All rights reserved.

Products

  • Scheduling
  • MedList
  • Provider Directory
  • Terminology
  • Synthetic Patients
  • Health Links
  • Decision Support
  • Drug Interaction
  • Device Data

Platform

  • Pricing
  • Docs
  • Contact

Legal

  • Terms
  • Privacy