diff --git a/doc/toolbox-create.1.md b/doc/toolbox-create.1.md
index ecde9f9..0e18615 100644
--- a/doc/toolbox-create.1.md
+++ b/doc/toolbox-create.1.md
@@ -82,7 +82,8 @@ confusion.
 **--distro** DISTRO, **-d** DISTRO
 
 Create a toolbox container for a different operating system DISTRO than the
-host. Cannot be used with `--image`.
+host. Cannot be used with `--image`. Has to be coupled with `--release` unless
+the selected DISTRO matches the host.
 
 **--image** NAME, **-i** NAME
 
diff --git a/doc/toolbox-enter.1.md b/doc/toolbox-enter.1.md
index 94180bc..fda0072 100644
--- a/doc/toolbox-enter.1.md
+++ b/doc/toolbox-enter.1.md
@@ -32,6 +32,7 @@ The following options are understood:
 **--distro** DISTRO, **-d** DISTRO
 
 Enter a toolbox container for a different operating system DISTRO than the
+host. Has to be coupled with `--release` unless the selected DISTRO matches the
 host.
 
 **--release** RELEASE, **-r** RELEASE
diff --git a/doc/toolbox-run.1.md b/doc/toolbox-run.1.md
index b8a2daa..e0dc098 100644
--- a/doc/toolbox-run.1.md
+++ b/doc/toolbox-run.1.md
@@ -34,7 +34,8 @@ entirely customized containers created from custom-built images.
 **--distro** DISTRO, **-d** DISTRO
 
 Run command inside a toolbox container for a different operating system DISTRO
-than the host.
+than the host. Has to be coupled with `--release` unless the selected system
+matches the host system.
 
 **--release** RELEASE, **-r** RELEASE