diff --git a/README.md b/README.md
index 2022320f..b57e9afd 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@
 # swagger-php
 
 Generate interactive [OpenAPI](https://www.openapis.org) documentation for your RESTful API using
-[doctrine annotations](https://www.doctrine-project.org/projects/annotations.html) (optional as of version 4.8)
+[doctrine annotations](https://www.doctrine-project.org/projects/annotations.html) (optional as of version 4.8; if required the `doctrine/annotations` library must be installed in addition to swagger.php).
 or [PHP attributes](https://www.php.net/manual/en/language.attributes.overview.php).
 
 For a full list of supported annotations, please have look at the [`OpenApi\Annotations` namespace](src/Annotations) or the [documentation website](https://zircote.github.io/swagger-php/guide/annotations.html).
@@ -46,6 +46,11 @@ composer global require zircote/swagger-php
 ### doctrine/annotations
 As of version `4.8` the [doctrine annotations](https://www.doctrine-project.org/projects/annotations.html) library **is optional** and **no longer installed by default**.
 
+To use PHPDoc annotations this needs to be installed on top of `swagger-php`:
+```shell
+composer require doctrine/annotations
+```
+
 If your code uses PHPDoc annotations you will need to install this as well:
 
 ```shell
diff --git a/docs/guide/faq.md b/docs/guide/faq.md
index bfceaf5b..c1346864 100644
--- a/docs/guide/faq.md
+++ b/docs/guide/faq.md
@@ -46,6 +46,13 @@ class OpenApiSpec
 }
 ```
 
+**As of version 4.8 the `doctrine/annotations` library is optional and might cause the same message.**
+
+If this is the case, `doctrine annotations` must be installed separately:
+```shell
+composer require doctrine/annotations
+```
+
 ## Annotations missing
 
 Another side effect of using reflection is that `swagger-php` _"can't see"_ multiple consecutive docblocks any more as the PHP reflection API only provides access to the docblock closest to a given structural element.