diff --git a/docs/fernet.rst b/docs/fernet.rst
index 4e618f5..68184b3 100644
--- a/docs/fernet.rst
+++ b/docs/fernet.rst
@@ -39,10 +39,13 @@
         :param bytes plaintext: The message you would like to encrypt.
         :returns bytes: A secure message which cannot be read or altered
                         without the key. It is URL-safe base64-encoded. This is
-                        refered to as a "Fernet token". Note that this contains
-                        the current time when it was generated in *plaintext*,
-                        the time a message was created will therefore be
-                        visible to a possible attacker.
+                        refered to as a "Fernet token".
+
+        .. warning::
+
+            The encrypted message contains the current time when it was
+            generated in *plaintext*, the time a message was created will
+            therefore be visible to a possible attacker.
 
     .. method:: decrypt(token, ttl=None)