diff --git a/core/js/multiselect.js b/core/js/multiselect.js
index ba89c1bb5632ff9a19bdb2f24248773fdb07eb98..c4fd74b0475e746844b554f23d9b94f487de8b45 100644
--- a/core/js/multiselect.js
+++ b/core/js/multiselect.js
@@ -129,13 +129,24 @@
 						if(event.keyCode == 13) {
 							event.preventDefault();
 							event.stopPropagation();
+							var value = $(this).val();
+							var exists = false;
+							$.each(options,function(index, item) {
+								if ($(item).val() == value) {
+									exists = true;
+									return false;
+								}
+							});
+							if (exists) {
+								return false;
+							}
 							var li=$(this).parent();
 							$(this).remove();
 							li.text('+ '+settings.createText);
 							li.before(createItem(this));
 							var select=button.parent().next();
 							var option=$('<option selected="selected"/>');
-							option.attr('value',$(this).val());
+							option.attr('value',value);
 							option.text($(this).val());
 							select.append(option);
 							li.prev().children('input').trigger('click');