diff --git a/src/Api.php b/src/Api.php
index f34040b..139269d 100644
--- a/src/Api.php
+++ b/src/Api.php
@@ -235,6 +235,20 @@ class Api
             }
 
             $query = array_merge($query, (array)$content);
+
+            // rewrite query args to properly dump true/false parameters
+            foreach($query as $key => $value)
+            {
+                if ($value === false)
+                {
+                    $query[$key] = "false";
+                }
+                elseif ($value === true)
+                {
+                    $query[$key] = "true";
+                }
+            }
+
             $query = \GuzzleHttp\Psr7\build_query($query);
 
             $url     = $request->getUri()->withQuery($query);
diff --git a/tests/ApiTest.php b/tests/ApiTest.php
index f9db6d9..7c74d34 100644
--- a/tests/ApiTest.php
+++ b/tests/ApiTest.php
@@ -364,7 +364,7 @@ class ApiTest extends \PHPUnit_Framework_TestCase
         //}));
 
         $api = new Api($this->application_key, $this->application_secret, $this->endpoint, $this->consumer_key, $this->client);
-        $api->get('/me/api/credential', ['dryRun' => true, 'noDryRun' => false]);
+        $api->get('/me/api/credential', ['dryRun' => true, 'notDryRun' => false]);
     }
 
 }