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Mononucleosis, or 'mono', is an extremely common viral infection caused by the Epstein-Barr virus (EBV). Most people will be infected at some time in their lives.  Mono frequently affects adolescents and young adults, especially when residing, studying and socializing in crowded settings, such as the university lifestyle.  Mono can be spread through contact with saliva, including eating or drinking after an infected person, or through kissing a contagious person. In the past, mono was called “the kissing disease” but kissing is only one way mono is spread.  It is difficult to accurately determine when or from whom a person caught mono. It generally takes 4–8 weeks for the first symptoms to appear.  Once someone has mono, they are likely to remain contagious for many weeks may continue to be contagious intermittently for decades.  Infection in early childhood is often asymptomatic or have only mild symptoms which may go unnoticed at that age.

Typical Mononucleosis Symptoms 

  • Swollen lymph glands in the front or sides of the neck
  • Fever (100.4 F / 38 C or greater)
  • Sore throat usually with swollen tonsils coated with white or grey-green material
  • Fatigue generally lasting 4–6 weeks
  • Headache
  • Loss of appetite
  • Jaundice (yellowing of the skin or whites of the eyes)
  • Rash 

You should contact the IU Health Center Medical Clinic if you experience any of these more serious symptoms:

  • Tonsil or throat swelling that causes difficulty swallowing or breathing
  • Pain in either side of the upper abdomen
  • Jaundice (yellowing of the skin or whites of the eye)
  • Chest pain
  • Unusual weakness in arms or legs
  • Severe headache
  • Stiff neck
  • Vision problems
  • Prolonged fatigue after 6 weeks

Mononucleosis Prevention

Since mono is spread in saliva, avoid eating or drinking from the same glasses, dishes or utensils of friends or strangers and at parties.  Do not share personal items or smoking products (but we advise everyone not to smoke).  Wash hands regularly, especially before eating.  Avoid sick people.  There is no medication or vaccine to prevent mono.

Mononucleosis Diagnosis

Mono can usually be quickly diagnosed by a IU Health Center medical provider examination and a blood test in the IU Health Center Laboratory while waiting. Occasionally, the test can be negative early in the illness even if symptoms are suspicious for mono and a follow up test several days to a week later may be required to confirm the diagnosis of mono.  A small percentage of people with mono continue to test negative.  Some persons have mono and a strep throat infection at the same time so tests for both may be indicated.

Mononucleosis Treatment

Mono is a virus, so it has to run its course.  Acute symptoms of mono can last 7–14 days or longer and improvement is gradual.  These is no cure and antivirals or antibiotics do not help.  Antibiotics only treat bacterial infections.  Taking some antibiotics with mono can cause a rash. 

Treatment consists of self-care and these things can help for feeling better:

  • Get plenty of rest to avoid prolonging or relapsing the illness.
  • Take acetaminophen (Tylenol) or ibuprofen (Advil, Motrin, etc.) for fever or pain. Taking more Acetaminophen (Tylenol) than recommended can cause liver damage. Thus it is important to closely follow the dosing instructions or the health care provider’s instructions to safely take this medication.  Check all medications for acetaminophen because it is combined with other ingredients.
  • Throat lozenges or spray containing benzocaine (such as Cepacol) may provide temporary relief from throat pain.
  • Gargle, then spit out, warm salt water for a sore throat (use 1/2 teaspoon of salt in 8 ounces of warm water).
  • Feeling ill often causes a loss of appetite. This is normal, and usually improves as the infection improves. It is important, even if no appetite, to drink an adequate amount of fluids. The urine will be a pale yellow when drinking enough fluids.

In addition to self-care, it is important to avoid strenuous activity and abstain from alcohol:

Avoid Strenuous Activity

People with mono should avoid sports, lifting, straining, falls, injury to the abdomen and physical exertion for about 4 weeks. That's because mono affects the spleen to some extent in about 50% to 60% of people with mono. An enlarged spleen is more vulnerable to rupture either spontaneously or from trauma to the abdomen.  A ruptured spleen is an emergency. The person with mono should get medical clearance before resuming regular activities.

Abstain From Alcohol

Mononucleosis often inflames the liver and alcohol makes this inflammation worse. Mono patients should not use alcohol for two months after the onset of symptoms.

Even the common symptoms of mono are frequently severe enough to warrant prescription medication for pain relief during the acute phase. If any concerns regarding the possibility of mono or complications from mono, call or schedule an appointment with an IU Health Center medical provider.