diff --git a/src/php/WPDiscuz/Base.php b/src/php/WPDiscuz/Base.php
index 43b5f647..992d5fc3 100644
--- a/src/php/WPDiscuz/Base.php
+++ b/src/php/WPDiscuz/Base.php
@@ -26,6 +26,10 @@ public function __construct() {
 	 * @noinspection PhpUndefinedFunctionInspection
 	 */
 	protected function init_hooks(): void {
+		if ( ! function_exists( 'wpDiscuz' ) ) {
+			return;
+		}
+
 		$wpd_recaptcha = wpDiscuz()->options->recaptcha;
 		$wpd_recaptcha = array_merge(
 			$wpd_recaptcha,