R4 Fhir

Name: R4 Fhir API
Brand: R4 Fhir
Availability: InStock

★ Only Publicly Available OpenAPI DocumentHealthcareEhr Emrbearer40 EndpointsREST

For Agents

Access electronic health records and clinical data through FHIR R4 standard resources. Retrieve patient demographics, medications, lab results, diagnoses, and immunizations.

Connect the R4 Fhir to your agent

Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the R4 Fhir, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.

Install Jentic One Beta (Self-Hosted)

Jentic One Host machine

# On the machine that will host your Jentic One instance:
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh

Agent machine

# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh
jentic register       # connects your agent to your Jentic One instance

Jentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.

Capabilities

What an agent can do with R4 Fhir API.

Retrieve patient demographics, contact information, and clinical identifiers

Query medication requests, statements, and prescription history

Access lab results and diagnostic reports with LOINC-coded observations

Fetch allergy and intolerance records with reaction severity

GET STARTED

Start building with R4 Fhir API

Explore with Jentic

View OpenAPI Document

Jentic publishes the only available OpenAPI document for R4 Fhir, keeping it validated and agent-ready.

NextGen's FHIR R4 API provides standardized access to electronic health records through 21 clinical resource types including Patient, Observation, MedicationRequest, and DiagnosticReport. Built on the HL7 FHIR R4 standard, the API enables RESTful read and search operations across allergy records, care plans, immunizations, lab results, and encounter data. Healthcare applications can retrieve structured clinical data in JSON format with OAuth 2.0 security to support care coordination, population health analytics, and patient engagement workflows.

Use Cases

Patterns agents use R4 Fhir API for, with concrete tasks.

★ Population Health Analytics

Healthcare organizations use the NextGen FHIR R4 API to aggregate clinical data across patient populations for quality reporting and analytics. The API enables bulk retrieval of structured observations, conditions, and procedures coded with standard terminologies like SNRX, ICD-10, and LOINC. Analytics platforms query the API to identify care gaps, track chronic disease management, and generate CMS quality measures. Integration typically requires 3-5 days for authentication, data mapping, and testing across the 21 available FHIR resource types.

Search for all patients with diabetes diagnosis (ICD-10 code E11) and retrieve their most recent HbA1c lab results from the past 6 months

Care Coordination Across Systems

Health information exchanges and care coordination platforms integrate with NextGen FHIR R4 API to synchronize patient records between organizations. The API supports real-time queries for care plans, care team assignments, and encounter summaries to enable transitions of care. Applications retrieve medication reconciliation data, active problems, and recent procedures to build comprehensive patient care records. The standard FHIR resource structure simplifies interoperability between NextGen and other FHIR-compliant EHR systems without custom data transformation.

Retrieve the active care plan, current medications, and assigned care team for patient ID 12345 to prepare for a transition of care to a specialist

Patient Engagement Applications

Mobile health apps and patient portals use the NextGen FHIR R4 API to give patients on-demand access to their own medical records. Applications authenticate via OAuth 2.0 patient-facing scopes to retrieve immunization records, lab results, visit summaries, and medication lists in consumer-friendly formats. The FHIR standard's patient compartment ensures queries automatically scope to the authenticated patient's data. Development teams implement the API in 2-4 days for read-only patient access workflows.

Retrieve immunization history, upcoming appointments, and latest lab results for the authenticated patient to display in a mobile health app dashboard

AI Agent Clinical Decision Support

AI agents integrate with NextGen FHIR R4 API through Jentic to power clinical decision support tools that require real-time EHR data access. Agents search by intent like 'retrieve patient allergies' or 'get recent lab values' and Jentic returns the matching FHIR operation with input schema. The agent executes queries for AllergyIntolerance, Observation, and MedicationRequest resources to check drug interactions, flag abnormal results, and identify care gaps. Through Jentic, OAuth credentials are isolated in the secure vault and agents receive scoped access tokens. Integration time drops from 5-7 days for direct FHIR implementation to under 2 hours via Jentic's intent-based discovery.

Search Jentic for 'retrieve patient medication list', load the MedicationRequest FHIR resource schema, and execute a query for active medications to check for drug-drug interactions before prescribing

Key Endpoints

40 endpoints — nextgen's fhir r4 api provides standardized access to electronic health records through 21 clinical resource types including patient, observation, medicationrequest, and diagnosticreport.

METHOD

PATH

DESCRIPTION

GET

/Patient/{id}

Retrieve a specific patient record by ID

GET

/Patient

Search for patients by name, identifier, or demographics

GET

/Observation/{id}

Get a specific lab result or vital sign observation

GET

/MedicationRequest

Search medication prescriptions by patient or date

GET

/Condition

Search patient conditions and diagnoses

GET

/AllergyIntolerance/{id}

Retrieve a specific allergy or intolerance record

GET

/DiagnosticReport

Search lab and imaging reports by patient

GET

/Immunization

Search immunization records by patient

GET

/Patient/{id}

Retrieve a specific patient record by ID

GET

/Patient

Search for patients by name, identifier, or demographics

GET

/Observation/{id}

Get a specific lab result or vital sign observation

GET

/MedicationRequest

Search medication prescriptions by patient or date

GET

/Condition

Search patient conditions and diagnoses

Why though Jentic?

Three things that make agents converge on Jentic-routed access.

Credential isolation

NextGen OAuth 2.0 tokens are stored encrypted in the Jentic vault. Agents receive scoped access tokens for read operations without direct access to the bearer credentials. Token refresh is handled automatically within the MAXsystem credential isolation layer.

Intent-based discovery

Agents search by clinical intent like 'retrieve patient allergies' or 'get lab results' and Jentic returns the matching FHIR resource (AllergyIntolerance, Observation) with search parameters and response schemas. This eliminates the need for developers to navigate FHIR capability statements or resource documentation.

Time to first call

Direct NextGen FHIR integration requires 5-7 days for OAuth setup, FHIR resource mapping, and terminology handling. Through Jentic, clinical AI agents integrate in under 2 hours by searching for intents, loading resource schemas, and executing queries without manual FHIR implementation.

Related APIs

Alternatives and complements available in the Jentic catalogue.

Alternative

Epic FHIR

Epic's FHIR R4 API serves the largest EHR market share with similar clinical resource coverage

Choose Epic FHIR when integrating with Epic EHR deployments at large hospital systems; choose NextGen FHIR for ambulatory and community health center workflows where NextGen is the primary EHR

Alternative

athenahealth API

athenahealth provides ambulatory EHR and practice management with REST API access to clinical data

Choose athenahealth API when working with athenaOne EHR deployments; choose NextGen FHIR for FHIR-standard interoperability and when NextGen is the EHR in use

Complementary

1upHealth FHIR

1upHealth aggregates FHIR data from multiple EHR sources into a unified patient record

Use 1upHealth alongside NextGen FHIR when you need to aggregate patient data from multiple EHR systems and payers; use NextGen FHIR directly for real-time queries against a NextGen EHR deployment

FAQs

Specific to using R4 Fhir API through Jentic.

What authentication does the NextGen FHIR R4 API use?

The API uses OAuth 2.0 Bearer token authentication. When integrating through Jentic, OAuth credentials are stored encrypted in the Jentic vault and agents receive scoped access tokens without exposing the raw bearer token. This follows FHIR's SMART on FHIR security framework for patient and provider-facing applications.

Can I retrieve patient lab results with the NextGen FHIR R4 API?

Yes, you can retrieve lab results through the Observation and DiagnosticReport resources. Query GET /Observation with patient parameter to fetch individual lab values coded with LOINC, or GET /DiagnosticReport to retrieve complete lab report bundles with multiple observations. Results include reference ranges, interpretation flags, and effective dates.

What are the rate limits for the NextGen FHIR R4 API?

Rate limits are not documented in the OpenAPI specification. NextGen typically enforces rate limits at the OAuth client level. Production integrations should implement exponential backoff for HTTP 429 responses and monitor the X-RateLimit headers if present. Contact NextGen support for specific rate limit policies for your use case.

How do I search for medications for a patient through Jentic?

Search Jentic with the intent 'retrieve patient medication list'. Jentic returns the MedicationRequest resource with its schema and search parameters. Execute a GET /MedicationRequest query with patient parameter to retrieve active and past prescriptions. The response includes medication codes, dosage, frequency, and prescriber details in FHIR-compliant JSON format.

Does the NextGen FHIR R4 API support write operations?

The NextGen FHIR R4 API documented in this specification supports read-only operations (GET requests). The 40 endpoints cover retrieval and search across 21 FHIR resource types. Write operations (POST, PUT, PATCH) for creating or updating clinical records are not included in the currently available specification. Check with NextGen for write access availability.

Which FHIR resources are available in the NextGen R4 API?

The API provides access to 21 FHIR R4 resources: Patient, Observation, MedicationRequest, MedicationStatement, Condition, AllergyIntolerance, Immunization, DiagnosticReport, Encounter, CarePlan, CareTeam, Procedure, Goal, DocumentReference, Device, Location, Organization, Practitioner, RelatedPerson, and Provenance. Each resource supports retrieval by ID and search with resource-specific parameters following the FHIR R4 specification.