Office/Word 2003 SP1 on Windows 2000 Professional

When working with a document containing index entries - {XE "index this"}-
sometimes the entries will suddenly appear in the text (in Normal and Print
Layout, but not Reading Layout). Show/Hide Formatting Marks has no affect on
this. Sometimes I can save and re-open and the index markers will then be
hidden (for a while), but is there a "Show/hide" menu option or button for
this?