diff --git a/flask_cache/__init__.py b/flask_cache/__init__.py
index 85d90e3..944c52f 100644
--- a/flask_cache/__init__.py
+++ b/flask_cache/__init__.py
@@ -661,7 +661,8 @@ def add(self, b):
 
         try:
             if not args and not kwargs:
-                self._memoize_version(f, reset=True)
+                _timeout = getattr(f, 'cache_timeout', None)
+                self._memoize_version(f, reset=True, timeout=_timeout)
             else:
                 cache_key = f.make_cache_key(f.uncached, *args, **kwargs)
                 self.cache.delete(cache_key)