diff --git a/platypush/message/request/__init__.py b/platypush/message/request/__init__.py
index 75cc9d09..66ce3fcb 100644
--- a/platypush/message/request/__init__.py
+++ b/platypush/message/request/__init__.py
@@ -159,12 +159,12 @@ class Request(Message):
                         'origin attached: {}'.format(response))
 
 
-    def execute(self, n_tries=1, async=True, **context):
+    def execute(self, n_tries=1, _async=True, **context):
         """
         Execute this request and returns a Response object
         Params:
             n_tries -- Number of tries in case of failure before raising a RuntimeError
-            async   -- If True, the request will be run asynchronously and the
+            _async   -- If True, the request will be run asynchronously and the
                        response posted on the bus when available (default),
                        otherwise the current thread will wait for the response
                        to be returned synchronously.
@@ -212,7 +212,7 @@ class Request(Message):
             if self.token is None or get_hash(self.token) != token_hash:
                 raise PermissionError()
 
-        if async:
+        if _async:
             Thread(target=_thread_func, args=(n_tries,)).start()
         else:
             return _thread_func(n_tries)
diff --git a/platypush/procedure/__init__.py b/platypush/procedure/__init__.py
index 56293176..2bef5b9f 100644
--- a/platypush/procedure/__init__.py
+++ b/platypush/procedure/__init__.py
@@ -108,7 +108,7 @@ class Procedure(object):
             context['async'] = self._async; context['n_tries'] = n_tries
             response = request.execute(**context)
 
-            if not self.async:
+            if not self._async:
                 if isinstance(response.output, dict):
                     for (k,v) in response.output.items():
                         context[k] = v