A mild case of mononucleosis would not look different from any other sore throat. In more severe cases, the patients develop large swollen glands in the neck, under the arms, and in the groin. They may have enlargement of the spleen. The tonsillitis associated with mononucleosis may be so severe that the tonsils swell to the point of touching and the patient is almost unable to swallow. Fatigue and dizziness are common symptoms which may last from weeks to months after the acute illness is over.
Fevers can be high and persist up to two weeks.
Sometimes mononucleosis causes jaundice. The diagnosis is obvious when a patient has all the classical findings of mononucleosis, but in less obvious cases the diagnosis can be made or confirmed with a blood test. The blood test may not be diagnostic until at least a week of illness. Since Mononucleosis is caused by a virus, there is no curative medicine available. The main treatment is bed rest and adequate fluids.