diff --git a/htdocs/admin/notification.php b/htdocs/admin/notification.php
index 2a401df047e..aa0a6a97852 100644
--- a/htdocs/admin/notification.php
+++ b/htdocs/admin/notification.php
@@ -448,7 +448,7 @@ foreach ($listofnotifiedevents as $notifiedevent) {
 	$inputfieldalreadyshown = 0;
 	// Notification with threshold
 	foreach ($conf->global as $key => $val) {
-		if ($val == '' || !preg_match('/^NOTIFICATION_FIXEDEMAIL_'.$notifiedevent['code'].'_THRESHOLD_HIGHER_(.*)/', $key, $reg)) {
+		if ($val == '' || !preg_match('/^NOTIFICATION_FIXEDEMAIL_'.preg_quote($notifiedevent['code'], '/').'_THRESHOLD_HIGHER_(.*)/', $key, $reg)) {
 			continue;
 		}