text: does mono last for six months ?   there is no definite time course for mononucleosis, but it can last several months.  when i had it in college it lasted about a month and a half and was mostly just a sore throat, but symptoms vary.  there are no antibiotics that will help, so treatment is mainly just rest and some analgesics.  however, the most important thing if you do have mono is to avoid contact sports as your spleen is very delicate and prone to rupture while you have mono.