diff --git a/lib/api/monitor.js b/lib/api/monitor.js
index b7f4b5d..44f4c9a 100644
--- a/lib/api/monitor.js
+++ b/lib/api/monitor.js
@@ -237,6 +237,8 @@ function mute(monitorId, options, callback){
         if(options.end){
             params.body.end = parseInt(options.end);
         }
+    } else {
+        params.body = "";  // create empty body
     }
     client.request("POST", util.format("/monitor/%s/mute"), params, callback);
 }
@@ -291,6 +293,11 @@ function unmute(monitorId, scope, callback){
         params.body = {
             scope: scope
         };
+<<<<<<< HEAD
+=======
+    } else {
+        params.body = "";  // create empty body
+>>>>>>> 5243bf7... add params.body default to client.prototype.request
     }
     client.request("POST", util.format("/monitor/%s/unmute", monitorId), params, callback);
 }
diff --git a/lib/client.js b/lib/client.js
index 9a9839c..f5b5ebc 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -49,10 +49,9 @@ var client = function(){
 client.prototype.request = function(method, path, params, callback){
     if(arguments.length === 3 && typeof arguments[2] === "function"){
         callback = arguments[2];
-        params = {};
+        params = {body: ''};  // create params with empty body property
     }
 
-    params = params || {};
     var body = (typeof params["body"] === "object") ? json.stringify(params["body"]) : params["body"];
     var query = {
         "api_key": this.api_key,