diff --git a/lib/fast_textile/parser.ex b/lib/fast_textile/parser.ex
index 81e9d429..5bc2754f 100644
--- a/lib/fast_textile/parser.ex
+++ b/lib/fast_textile/parser.ex
@@ -82,6 +82,11 @@ defmodule FastTextile.Parser do
   #
   #   open_token callback* close_token (?!lookahead_not)
   #
+  defp simple_lookahead_not(open_token, _close_token, _open_tag, _close_tag, _lookahead_not, _callback, _state, _parser, [{open_token, open}, {forbidden_lookahead, t} | r_tokens])
+    when forbidden_lookahead in [:space, :newline]
+  do
+    {:ok, [{:text, escape(open)}], [{forbidden_lookahead, t} | r_tokens]}
+  end
   defp simple_lookahead_not(open_token, close_token, open_tag, close_tag, lookahead_not, callback, state, parser, [{open_token, open} | r_tokens]) do
     case parser.state do
       %{^state => _} ->