diff --git a/options_element.module b/options_element.module
index 62ad4ab..71bca57 100644
--- a/options_element.module
+++ b/options_element.module
@@ -277,6 +277,7 @@ function _options_element_add_allowed_values_element(&$form, $element) {
     '#key_type_toggled' => TRUE,
     '#after_build' => array('options_element_field_settings_after_build'),
     '#access' => $form['field']['settings']['allowed_values']['#access'],
+    '#default_value' => '',
     // Pass original data for validating
     '#original' => array(
       '#title' => $form['field']['settings']['allowed_values']['#title'],