FHIR R4 Overview

FHIR R4 is typically used for:

Point-of-care data access
Patient-centric clinical data retrieval
Integration with modern FHIR-native systems

All resources follow the HL7 FHIR R4 specification, with Health Gorilla–specific extensions where applicable. The API Reference lists the supported operations per resource.

Tip: If your calls begin with /fhir/R4/..., you’re using the FHIR R4 version of the API.

Base URLs

FHIR R4 endpoints are accessed using a common base URL per environment. Resource paths are appended to the base URL (for example, /Patient, /Observation).

Environment	Base URL
Sandbox	`https://sandbox.healthgorilla.com/fhir/R4`
Production	`https://api.healthgorilla.com/fhir/R4`

Authentication

All FHIR R4 API requests require OAuth 2.0 authentication using a bearer token. Requests without a valid access token return 401 Unauthorized responses.

Access scopes are resource-specific (for example, patient.read, condition.write) and are documented on each resource page.

For details on token acquisition and scope configuration, see OAuth 2.0 Authentication.

Scope and Behavior

This overview describes the general behavior of the Health Gorilla FHIR R4 interface. Individual resource pages document resource-specific fields, search parameters, and supported operations.

Health Gorilla supports a subset of the HL7 FHIR R4 specification. Not all optional elements defined in the HL7 standard may be stored, indexed, or returned. Unsupported or unrecognized elements may be ignored or normalized during processing.

Clinical data exposed via FHIR R4 may be aggregated from connected systems and normalized for longitudinal review, depending on enabled products and configuration.

Search and Pagination

Search operations return results as a FHIR Bundle resource.
Searches are scoped to the authenticated tenant.
Pagination may be applied to large result sets. Use standard FHIR pagination links provided in Bundle.link to retrieve additional pages.
For patient-centric workflows, including a patient search parameter is recommended when supported by the resource.

FHIR R4 Resource Capabilities

The table below summarizes the operations documented for FHIR R4 resources in the Health Gorilla API Reference and highlights the Health Gorilla solutions where each resource is commonly surfaced in client-facing workflows.

Associated solutions are illustrative and non-exhaustive. Resource availability and behavior depend on enabled products, configuration, and granted scopes.

Legend: ✔ supported operation

Resource	Read	Search	Create	Update	Delete	Download PDF†	Special Operations	Associated Solutions
`AllergyIntolerance`	✔	✔	✔	✔	✔			Patient360
`Bundle`							Batch, Document, Transaction	Platform / internal workflows
`CarePlan`	✔	✔	✔	✔	✔			Patient360
`Composition`	✔	✔					Document (GET)	Patient360
`Condition`	✔	✔	✔	✔	✔			Patient360
`Consent`	✔	✔	✔		✔			Patient360
`Coverage`	✔	✔	✔		✔			Patient360
`DeviceUseStatement`	✔	✔	✔	✔	✔			Patient360
`DiagnosticReport`	✔	✔	✔			✔		Patient360, Lab Network
`DocumentReference`	✔	✔	✔		✔	✔		Patient360, Clinical Alerts
`Encounter`	✔	✔	✔	✔	✔			Patient360, Clinical Alerts
`FamilyMemberHistory`	✔	✔	✔	✔	✔			Patient360
`Goal`	✔	✔	✔	✔	✔			Patient360
`Immunization`	✔	✔	✔	✔	✔			Patient360
`Location`	✔	✔						All solutions
`MedicationDispense`	✔	✔	✔	✔	✔			Patient360
`MedicationRequest`	✔	✔	✔	✔	✔			Patient360
`MedicationStatement`	✔	✔	✔	✔	✔			Patient360
`NutritionOrder`	✔	✔	✔	✔	✔			Patient360
`Observation`	✔	✔	✔	✔	✔			Patient360, Lab Network
`Organization`	✔	✔	✔	✔	✔			All solutions
`Patient`	✔	✔	✔	✔			`$everything` (GET)	Patient360, Clinical Alerts, Lab Network
`Practitioner`	✔	✔						All solutions
`PractitionerRole`	✔	✔	✔	✔				All solutions
`Procedure`	✔	✔	✔	✔	✔			Patient360
`Provenance`							Listed for reference; operation support is limited and not documented in this overview	Platform / internal attribution and auditing
`RequestGroup`	✔	✔	✔			✔		Lab Network
`ServiceRequest`	✔	✔	✔			✔		Lab Network

† The Download PDF column applies to resource-level document retrieval and does not apply to patient-scoped export or aggregation operations.

Notifications

The FHIR R4 API does not provide direct resource-level subscriptions. Changes to clinical data may surface through broader notification workflows depending on enabled Health Gorilla products and configuration. For details, see Webhooks & Notifications.

Error Handling

FHIR R4 operations return structured errors using the HL7 OperationOutcome resource.

HTTP status codes are used to indicate request success or failure (for example, 400 Bad Request, 401 Unauthorized, 403 Forbidden, 404 Not Found). For more information, see Error Handling.

Notes

Operation support varies by resource. Use the API Reference operations listed under each resource as the source of truth.
“Download PDF” is a resource-specific GET operation where documented (for example, DiagnosticReport, DocumentReference, RequestGroup, and ServiceRequest).
Patient-level aggregation using the FHIR standard is documented under Patient/$everything (GET).