diff --git a/lib/db/caches.php b/lib/db/caches.php
index cd69bbccd11..38038eadb80 100644
--- a/lib/db/caches.php
+++ b/lib/db/caches.php
@@ -382,9 +382,6 @@ $definitions = array(
         'mode' => cache_store::MODE_SESSION,
         'simplekeys' => true,
         'simpledata' => true,
-        'ttl' => 1800,
-        'invalidationevents' => array(
-            'createduser',
-        )
+        'ttl' => 1800
     ),
 );
diff --git a/user/lib.php b/user/lib.php
index 7bb4f5f4070..ea1c1cb829a 100644
--- a/user/lib.php
+++ b/user/lib.php
@@ -126,8 +126,9 @@ function user_create_user($user, $updatepassword = true, $triggerevent = true) {
         \core\event\user_created::create_from_userid($newuserid)->trigger();
     }
 
-    // Purge the associated caches.
-    cache_helper::purge_by_event('createduser');
+    // Purge the associated caches for the current user only.
+    $presignupcache = \cache::make('core', 'presignup');
+    $presignupcache->purge_current_user();
 
     return $newuserid;
 }