diff --git a/Doc/howto/regex.rst b/Doc/howto/regex.rst
index eab23af..81d5aba 100644
--- a/Doc/howto/regex.rst
+++ b/Doc/howto/regex.rst
@@ -600,7 +600,7 @@
 
 .. data:: U
           UNICODE
-   :index:
+   :noindex:
 
    Make ``\w``, ``\W``, ``\b``, ``\B``, ``\d``, ``\D``, ``\s`` and ``\S``
    dependent on the Unicode character properties database.