diff --git a/lib/pleroma/web/activity_pub/activity_pub.ex b/lib/pleroma/web/activity_pub/activity_pub.ex
index 5c61920e5..a5e42d9d0 100644
--- a/lib/pleroma/web/activity_pub/activity_pub.ex
+++ b/lib/pleroma/web/activity_pub/activity_pub.ex
@@ -445,7 +445,7 @@ defp restrict_blocked(query, %{"blocking_user" => %User{info: info}}) do
       activity in query,
       where: fragment("not (? = ANY(?))", activity.actor, ^blocks),
       where: fragment("not (?->'to' \\?| ?)", activity.data, ^blocks),
-      where: fragment("not (? ~ ANY(?))", activity.actor, ^domain_blocks)
+      where: fragment("not (split_part(?, '/', 3) = ANY(?))", activity.actor, ^domain_blocks)
     )
   end
 
diff --git a/priv/repo/migrations/20180606173637_create_apid_host_extraction_index.exs b/priv/repo/migrations/20180606173637_create_apid_host_extraction_index.exs
new file mode 100644
index 000000000..9831a1b82
--- /dev/null
+++ b/priv/repo/migrations/20180606173637_create_apid_host_extraction_index.exs
@@ -0,0 +1,8 @@
+defmodule Pleroma.Repo.Migrations.CreateApidHostExtractionIndex do
+  use Ecto.Migration
+  @disable_ddl_transaction true
+
+  def change do
+    create index(:activities, ["(split_part(actor, '/', 3))"], concurrently: true, name: :activities_hosts)
+  end
+end