# Retrieve a patient's vaccination history

You can use this API action to access a list of a patient’s vaccinations, as documented by a specific organization. 

With this API action, you can retrieve information like dose, manufacturer, lot, route number, and more.

> **Prerequisite: Having a patient identifier**
>
> To use this API action, you must know the patient identifier. If you don’t have one, [search for a patient with demographics](/fhir-api-actions/patients/search-for-a-patient-by-demographics) to locate an appropriate identifier first.

## Use cases

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

- Track a patient’s vaccinations.
- Offer targeted recommendations for immunizations to patients.

## Supported systems

You can use this API action with the Redox FHIR API.

Your connection's system can return results with their own FHIR or query-based API. 

## Things you need to know

<details>
<summary>Organization-specific for vaccinations</summary>

You can only search and receive vaccination data from one organization for one patient, unless you’re requesting data from a state registry or similar network. If you want a more comprehensive list, you must perform this API action for every organization you’re interested in receiving data from. 

</details>

<details>
<summary>Vaccination codes</summary>

Vaccinations are typically represented in RxNorm, National Drug Code (NDC), or Vaccine Administered Code Set (VCX) codes.  

</details>

<details>
<summary>Refused vaccinations</summary>

Sometimes a provider recommends a vaccination that the patient declines. However, the provider still documents the offered vaccination. Depending on the connection's system, it might be difficult to tell that the vaccination wasn’t actually administered. 

We recommend that you check the status of the vaccination to determine whether a vaccination was administered. If a status is present, it should contain a reason for _not_ administering a vaccination. If a status isn’t present, it’s likely that the vaccination was administered.

</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.