Mononucleosis, or “mono”, is called the kissing disease because it is spread through a virus in your saliva. You can get it from kissing someone who is infected, sharing a toothbrush, or drinking from someone else's glass. Mono is spread from person to person, but it is harder to catch than the common cold. For most people mono is not a dangerous disease.

Symptoms of Mononucleosis

Symptoms of mono are most common in teenagers. Children can get mono, but they usually have very mild symptoms. Most adults have already been infected with the virus that causes mono. Once you have been infected, you build up a resistance to the virus and you don't get symptoms from it. The most common symptoms include:

  • Fatigue
  • Sore throat
  • Fever
  • Swollen glands
  • Muscle aches
  • Headache
  • Large tonsils with white patches
  • Trouble swallowing
  • Loss of appetite
  • Rash, and
  • Night sweats

Causes of Mono

Mono is usually caused by a virus called the Epstein-Barr virus. However, some other viruses may also cause mono, including a virus called cytomegalovirus, or CMV, and Human Immunodeficiency Virus, or HIV.

Epstein-Barr virus is so common that most adults have been infected by middle age. Most people who are infected with Epstein-Barr virus do not get symptoms of mono, but up to half of teenagers do.


Mono may be suspected when a teenager has symptoms. Mono may cause your liver or spleen to enlarge. Your health care provider will look for these signs during a physical exam. Blood tests are an important part of the diagnosis.

  • After about one week, people with mono build up antibodies to Epstein-Barr virus that can be detected with a rapid blood test called the monospot test.
  • A blood test called a complete blood count may show an increase in the number of white blood cells, which occurs in infections such as mono.
  • A more accurate blood test, an antibody titer, looks for different types and amounts of Epstein-Barr virus antibodies.

Risk Factors and Complications

Most people do not have any complications from mono. However, possible complications could include:

  • An enlarged spleen that ruptures and causes internal bleeding
  • An enlarged liver that leads to yellowing of the skin and eyes, called jaundice
  • Strep throat due to a bacterial infection

Less common complications include anemia, bleeding, heart problems, and nervous system problems.

Treatment Options

Because mono is caused by a virus, antibiotics won't make it go away. The only treatment is to rest, drink plenty of fluids, and take medication to reduce pain and fever. Symptoms usually clear up in about six weeks.

If enlarged tonsils make it hard to swallow, your health care provider may prescribe strong anti-inflammatory drugs called steroids. If you get strep throat, you may be treated with antibiotics.


It’s not possible to prevent mono because many people carry the Epstein-Barr virus infection. Isolating people with mono won't help. Once you have been infected, the Epstein-Barr virus stays in your system and you can spread it to someone else. Most infections are spread by people who don't have any symptoms.

Lifestyle Remedies

If you get mono, these steps will help:

  • Get plenty of rest.
  • Drink lots of fluids.
  • Take an over-the-counter pain reliever. However, children under 16 should not take aspirin.
  • Gargle with warm, salted water to ease a sore throat. Mix a 1/2 teaspoon of salt into 8 ounces of water.
  • Avoid any contact sports and strenuous activities until cleared by your health care provider.
  • Let your health care provider know if you have sudden pain in your left upper belly or any difficulty swallowing or breathing.

What We Have Learned

You can get mono from kissing someone who is infected, sharing a toothbrush, or drinking from someone else's glass.
True or False
The answer is True

The only treatment for mono is to rest, drink plenty of fluids, and take medication to reduce pain and fever.
True or False
The answer is True

If you have mono, you can continue playing contact sports or doing strenuous activities.
True or False
The answer is False