Infectious Mononucleosis

Infectious mononucleosis (mono) is a common germ (viral) infection in children, teenagers, and young adults.


Mono is an infection caused by the Epstein Barr virus. The virus is spread by close personal contact with someone who has the infection. It can be passed by contact with your saliva through things such as kissing or sharing drinking glasses. Sometimes, the infection can be spread from someone who does not appear sick but still spreads the virus (asymptomatic carrier state).


The most common symptoms of Mono are:

  • Sore throat.

  • Headache.

  • Fatigue.

  • Muscle aches.

  • Swollen glands.

  • Fever.

  • Poor appetite.

  • Enlarged liver or spleen.

The less common symptoms can include:

  • Rash.

  • Feeling sick to your stomach (nauseous).

  • Abdominal pain.


Mono is diagnosed by a blood test.


Treatment of mono is usually at home. There is no medicine that cures this virus. Sometimes hospital treatment is needed in severe cases. Steroid medicine sometimes is needed if the swelling in the throat causes breathing or swallowing problems.


  • Drink enough fluids to keep your urine clear or pale yellow.

  • Eat soft foods. Cool foods like popsicles or ice cream can soothe a sore throat.

  • Only take over-the-counter or prescription medicines for pain, discomfort, or fever as directed by your caregiver. Children under 18 years of age should not take aspirin.

  • Gargle salt water. This may help relieve your sore throat. Put 1 teaspoon (tsp) of salt in 1 cup of warm water. Sucking on hard candy may also help.

  • Rest as needed.

  • Start regular activities gradually after the fever is gone. Be sure to rest when tired.

  • Avoid strenuous exercise or contact sports until your caregiver says it is okay. The liver and spleen could be seriously injured.

  • Avoid sharing drinking glasses or kissing until your caregiver tells you that you are no longer contagious.


  • Your fever is not gone after 7 days.

  • Your activity level is not back to normal after 2 weeks.

  • You have yellow coloring to eyes and skin (jaundice).


  • You have severe pain in the abdomen or shoulder.

  • You have trouble swallowing or drooling.

  • You have trouble breathing.

  • You develop a stiff neck.

  • You develop a severe headache.

  • You cannot stop throwing up (vomiting).

  • You have convulsions.

  • You are confused.

  • You have trouble with balance.

  • You develop signs of body fluid loss (dehydration):

  • Weakness.

  • Sunken eyes.

  • Pale skin.

  • Dry mouth.

  • Rapid breathing or pulse.


  • Understand these instructions.

  • Will watch your condition.

  • Will get help right away if you are not doing well or get worse.