diff --git a/bin/cqlsh b/bin/cqlsh
index 1b282bd96f..22edde689e 100755
--- a/bin/cqlsh
+++ b/bin/cqlsh
@@ -246,7 +246,7 @@ cqlsh_extra_syntax_rules = r'''
 <debugCommand> ::= "DEBUG" "THINGS"?
                  ;
 
-<helpCommand> ::= ( "HELP" | "?" ) [topic]=( <identifier> | <stringLiteral> )*
+<helpCommand> ::= ( "HELP" | "?" ) [topic]=( /[a-z_]*/ )*
                 ;
 
 <exitCommand> ::= "exit" | "quit"