diff --git a/octoprint_gcode_macro/__init__.py b/octoprint_gcode_macro/__init__.py
index d374ebe..5a5b35a 100644
--- a/octoprint_gcode_macro/__init__.py
+++ b/octoprint_gcode_macro/__init__.py
@@ -109,7 +109,9 @@ def render_macro(self, command, level=0):
                 for cmd in commands:
                     if cmd.startswith("@"):
                         # Recursively render for each @ command in macro
-                        result += self.render_macro(cmd, level=level + 1)
+                        submacro = self.render_macro(cmd, level=level + 1)
+                        if submacro:
+                            result += submacro
                     else:
                         result += [cmd]
             else: