Mononucleosis — commonly called mono — is an infection caused by a virus (a type of germ). Kids with mono usually have a sore throat, have swollen glands (lymph nodes) in the neck, feel tired, and have a fever. They may also have a rash. Some kids with mono get a swollen spleen, so it's important to protect the spleen from injury for a few weeks. 

There is no treatment for mono, but the symptoms usually go away within a few weeks. In some kids, the tiredness can last longer. 

Follow your health care provider's advice for:

• Whether it's OK to give medicine for pain or fever, such as acetaminophen (Tylenol^® or a store brand) or ibuprofen (Advil^®, Motrin^®, or a store brand). Follow the package directions for how much to give and how often. Do not give aspirin to your child or teen, as it has been linked to a rare but serious illness called Reye syndrome.
• Avoiding activities that could cause injury to the spleen (such as contact sports, rough play, or heavy lifting) for several weeks.
• When it's OK for your child to return to all activities and sports.
• When to follow up.

General care: 

• Let your child rest as much as needed.
• Give your child plenty of liquids. 
• To relieve a sore throat:
  • Offer warm or cool liquids to drink, whichever is more soothing.
  • Offer soft foods that are easy to swallow.
  • Avoid salty, spicy, crunchy, or acidic foods (like citrus fruits). These can irritate a sore throat.
  • If your child is over 4 years old, give hard candy or a lozenge. Kids can choke on these, so only give them when they are awake and sitting up.
  • If your child is over 6 years old, have them gargle with a little saltwater 4–6 times a day. To make the saltwater, mix ¼ teaspoon of salt in 8 ounces of warm water. 
• When your health care provider says it's OK for your child to go back to all activities including sports, help them start slowly. It will take a while for them to have the same energy and strength they had before.

Your child:

• Has new or worsening symptoms
• Has a fever that:
  • Is getting higher
  • Hasn't gone away within a few days
  • Goes away then comes back
• Gets yellow skin or eyes
• Isn't drinking at all or has signs of dehydration (not enough water in the body) such as a dry or sticky mouth, sunken eyes, making less pee or darker than usual pee, or crying with little or no tears
• Doesn't seem to be getting better within a few weeks

Your child:

• Has belly, chest, or back pain, especially if it's sharp and comes on suddenly
• Is pale, faint, or dizzy
• Has trouble swallowing or breathing
• Develops weakness of the arms or legs
• Has a severe headache or stiff neck

How do kids get mono? Mono is caused by a virus called Epstein–Barr virus (EBV). It spreads through contact with saliva (spit). It is usually spread through coughing, sneezing, kissing, or sharing eating utensils, straws, or drinking glasses. 

Can someone get mono more than once? Most people don't get mono from EBV more than once. But they can get a mono-like illness from other types of viruses.

Is my child contagious? Yes, kids with mono spread the virus and sometimes it's not easy to tell when they are no longer contagious. They can help lower the risk of infecting someone else by washing their hands well and often and not sharing eating utensils, straws, or drinking glasses. 

Will an antibiotic help my child get better faster? Antibiotics treat bacteria, not viruses. Since mono is caused by a virus, an antibiotic won't help.