How long is it supposed to it take for mono/glandular fever to go?

Depends on immune sy. How long it takes mononucleosis or glandular period to go away depends on your immune system and varies from person to person. Some people feel better in days, some weeks and others it may take months.I will say if you have to take an average caase it may be4 to 6 weeks before all symptoms are gone but it is not the rule.