diff --git a/systemd-journal-gelf b/systemd-journal-gelf
index 3f8ccbb..bc68ce7 100644
--- a/systemd-journal-gelf
+++ b/systemd-journal-gelf
@@ -168,7 +168,7 @@ while ( my $entry = <JOURNAL> ){
   # OR
   #
   # gelf(~):code=200~url=/index.html~remote_ip=10.99.5.12~referer=http://test.local/
-  if ( $msg->{MESSAGE} =~ m/^gelf(\([^\(\)]+\))?:([a-zA-Z\d]+=([^\|])\|?)+/ ){
+  if ( $msg->{MESSAGE} =~ m/^gelf(\([^\(\)]+\))?:([a-zA-Z\d_\-]+=([^\|])\|?)+/ ){
     $msg->{MESSAGE} =~ s/^gelf(\([^\(\)]+\))?://;
     my $separator = ($1 && length $1 > 0) ? qr{$1} : qr{\|};
     foreach ( split /$separator/, $msg->{MESSAGE} ){