# Receive and respond to prior authorization

You can use this API action to process and respond to prior authorization requests. To kick off your workflow, your connection must [submit a prior authorization request](/fhir-api-actions/financial/submit-prior-authorization). 

## Use cases

This API action may be a good fit for your organization if you perform any of these use cases:

- Approve or decline prior authorization requests.
- Streamline or digitize your process for receiving prior authorization requests.

[Check out our case study](https://redoxengine.com/case-studies/prior-authorization/) for more details about the problems you can solve with this API action. 

## Supported systems

You can use this API action with a query-based API that can also exchange X12. Your responses to prior authorization requests can be either synchronous or asynchronous, depending on your own system’s capabilities. 

## Things you need to know

<details>
<summary>Support for service and prescription requests</summary>

Redox supports exchanging prior authorizations for either <u>services</u> or <u>prescriptions</u>, so you can respond to both kinds of requests.

</details>

<details>
<summary>Implementation notes for payers and vendors</summary>

We recommend that you [review the `Claim$submit-preauthorization` schema](https://docs.redoxengine.com/permalink/8aeb2d01-091b-5bb2-ab4b-515151c54d33-$submit-preauthorization) for two reasons.

First, you should make sure you can support all the required data points to receive a prior authorization request.

Second, you should confirm that it contains all the data your organization requires to process and approve a prior authorization request.

</details>

<details>
<summary>Payer prior authorization codes</summary>

HIPAA uses the X12 data standard, so your connection must use Current Procedural Terminology (CPT) codes to designate outpatient services or procedures in the prior authorization request. For medication, equipment, or supplies for treatment, your connection must use Healthcare Common Procedure Coding System (HCPCS), Level II codes. Make sure that you can support each of these code sets.

[Learn more about these code sets](https://www.cms.gov/outreach-and-education/medicare-learning-network-mln/mlnproducts/downloads/icd9-10cm-icd10pcs-cpt-hcpcs-code-sets-educational-tool-icn900943.pdf).

</details>

<details>
<summary>Filtering not supported</summary>

You receive prior authorization data within the FHIR `Claim` resource. While we generally support filters to reduce unwanted messages, we don’t support applying comprehensive business logic or rules to incoming `Claim` data. 

[Learn about filters](/how-to-use-redox/define-and-manage-filters).

</details>

> **What's next? **
>
> Does this API action seem like a good fit for your unique workflow? Let your Technical Account Manager know! To start development, download the resource schema noted in the related action step. Then decide which data elements you need.
>
> If you’re new to Redox, [use the Quickstart guide](/quickstart-for-redox) to dive in. If you’re not engaged with our sales team yet, [talk to a Redoxer](https://redoxengine.com/forms/contact-us/) to get started.