Glandular fever

Glandular fever mostly affects teenagers and young adults. It gets better without treatment. But it can make you feel very ill and last for weeks. It is sometimes known as infectious mononucleosis or mono.

Symptoms of glandular fever

Common symptoms of glandular fever include:

These are some of the symptoms of glandular fever. You do not usually get glandular fever more than once.

Glandular fever complications

Most people get over glandular fever with no problems. But sometimes glandular fever may lead to other illnesses. These include:

  • lower level of blood cells, such as anaemia
  • an infection, such as pneumonia
  • a neurological illness, such as Guillain-Barre syndrome or Bell's palsy

How to stop glandular fever spreading

Glandular fever is very infectious. It's passed in saliva and can be spread through:

  • kissing - it is often referred to as the 'kissing disease'
  • exposure to coughs and sneezes
  • sharing eating and drinking utensils, such as cups, glasses and unwashed forks and spoons

You are infectious for up to 7 weeks before you get symptoms.

To prevent glandular fever spreading:

  • wash hands regularly
  • wash bedding and clothes that may have spit on them
  • do not kiss others
  • do not share cups, cutlery or towels

Non-urgent advice: See a GP if you have:

  • a very high temperature or you feel hot and shivery
  • a severe sore throat
  • swelling either side of your neck - swollen glands
  • extreme tiredness or exhaustion
  • tonsillitis that is not getting better
  • a pain in your tummy

Tests for glandular fever

Sometimes it is difficult to tell the difference between glandular fever and other illnesses, like Strep throat or tonsillitis.

Your GP might arrange tests to confirm it's glandular fever. This would include a blood test for the Epstein-Barr virus. The Epstein-Barr virus causes glandular fever.

The tests may not be reliable in the early stages of the illness.

Immediate action required: Call 999 or go to your emergency department (ED) if you have:

  • difficulty swallowing
  • difficulty breathing
  • extreme tummy pain

Treatment for glandular fever

There's no cure for glandular fever. It gets better by itself.

You should:

  • rest and sleep
  • drink plenty of fluids to avoid dehydration
  • take painkillers like paracetamol or ibuprofen


Do not give aspirin to children under 16 years old.

Antibiotics and glandular fever

Antibiotics won't work for treating glandular fever. This is because glandular fever is caused by a virus. 

Returning to normal activities after glandular fever

You should feel better within 2 to 3 weeks. Some people might feel extremely tired for months. Try to gradually increase your activity when your energy starts to come back.

School and work

You can go back to school or work as soon as you start to feel better.

Glandular fever and sports

Glandular fever can cause your spleen to swell. For the first month, avoid sports or activities that might increase your risk of falling, as this may damage your spleen.

Glandular fever and alcohol

Don't drink alcohol if you have glandular fever. This is because your liver might be weak while you are ill.

Content supplied by the NHS and adapted for Ireland by the HSE

Page last reviewed: 26 April 2020
Next review due: 26 April 2023

This project has received funding from the Government of Ireland’s Sláintecare Integration Fund 2019 under Grant Agreement Number 123.