> For the complete documentation index, see [llms.txt](https://support.who-umc.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.who-umc.org/vigilyze/searching-and-filtering/search-by-atc.md).

# Search by ATC

ATC view allows drugs to be searched using the Anatomical Therapeutic Chemical (ATC) classification system.

To search using ATC:

1. Click **Filter** → **Drug** → **ATC view**.
2. Navigate through the classification levels using the expand arrows or use the ATC search bar.
3. Select the ATC level.
4. Click **Save**.

All products within the selected ATC level are included in the search.

{% hint style="info" %}
Selecting higher ATC levels provides broader results, while selecting more specific levels provides more targeted results.
{% endhint %}


---

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