Quick answer
What is glandular fever?
Glandular fever is a viral infection usually caused by Epstein-Barr virus (EBV), common in teenagers and young adults. It causes severe sore throat, swollen neck glands, fever, and fatigue that can last weeks to months. Most people recover fully without specific treatment — rest, fluids, and paracetamol or ibuprofen. Avoid contact sports for at least 4 weeks because of spleen enlargement risk.
Glandular fever — infectious mononucleosis
Glandular fever (medically infectious mononucleosis, often called mono) is a viral illness most commonly caused by Epstein-Barr virus (EBV). It is especially common in teenagers and young adults — though many people catch EBV earlier in life with mild symptoms or none at all.
The illness is famous for severe tiredness that outlasts the sore throat — recovery is often measured in weeks to months, not days.
Symptoms
Typical presentation:
- severe sore throat — can mimic bacterial tonsillitis
- swollen lymph nodes — especially neck; may be armpits and groin too
- high temperature and flu-like aches
- profound fatigue — often the most disabling symptom
- swollen, puffy eyelids sometimes
- headache, loss of appetite
Less common:
- rash — especially if given amoxicillin or ampicillin before diagnosis
- jaundice — mild liver involvement (yellow skin/eyes)
- enlarged spleen — felt as fullness left upper abdomen
- enlarged liver
Not everyone gets all symptoms — some have mild sore throat and fatigue only.
How it spreads
EBV spreads through saliva:
- kissing
- sharing drinks, cups, or cutlery
- coughs and sneezes (less than flu)
The virus has a long incubation period — 4 to 6 weeks from exposure to symptoms.
You are most infectious when acutely unwell, but the virus can be shed for months — reason to avoid sharing utensils while ill.
Diagnosis
GP may diagnose clinically in a young person with classic features. Blood tests confirm:
- Monospot test — rapid but can be false negative early
- EBV serology — IgM and IgG antibodies
Full blood count often shows atypical lymphocytes — characteristic white cell pattern.
Throat swab may be done to exclude strep throat — glandular fever is viral, so antibiotics do not cure it (except the rash issue below).
Treatment — supportive care
No antiviral cure for EBV in otherwise healthy people. Treatment is:
- rest — listen to fatigue; do not push through
- fluids — prevent dehydration, especially if swallowing is painful
- paracetamol or ibuprofen — fever, pain, throat inflammation
- throat lozenges, warm drinks, ice lollies — comfort
- avoid alcohol — liver is often inflamed
Steroids — occasionally used for severe airway swelling — specialist decision only.
Do not take amoxicillin or ampicillin if glandular fever is suspected or confirmed — causes widespread rash in most EBV cases.
Complications — rare but important
| Complication | Notes |
|---|---|
| Splenic rupture | Life-threatening — avoid contact sport; seek emergency care for sudden severe left-sided abdominal pain |
| Airway obstruction | Massive tonsil swelling — rare; may need steroids or hospital |
| Severe hepatitis | Uncommon |
| Chronic fatigue | Post-viral fatigue syndrome in some — overlaps with long recovery |
| Secondary bacterial infection | Tonsillar bacterial superinfection — rare |
Sport and exercise — critical advice
Enlarged spleen is common and not always obvious on examination.
Avoid for at least 4 weeks from onset:
- rugby, football, martial arts, boxing
- heavy weightlifting
- any activity with abdominal trauma risk
Return to sport only when GP confirms spleen has returned to normal size if previously enlarged.
Glandular fever vs other illnesses
| Condition | How it differs |
|---|---|
| Strep tonsillitis | Often no marked fatigue; responds to antibiotics; no EBV rash with amoxicillin |
| COVID-19 / flu | Different pattern; test if suspected |
| Cytomegalovirus (CMV) | Similar mono-like illness — blood tests distinguish |
| HIV acute seroconversion | Mono-like illness — HIV test if risk factors |
| Lymphoma | Persistent painless nodes, night sweats, weight loss — GP excludes if doubt |
See our swollen glands guide if nodes persist beyond expected recovery.
Recovery timeline
Week 1 to 2: Peak symptoms — throat, fever, glands.
Week 2 to 4: Throat and fever usually improve; fatigue often worsens or plateaus.
Month 2 to 6: Gradual energy return — non-linear; good days and bad days.
Return to normal: Most fully recover within 2 to 3 months; a minority have fatigue longer — worth GP review if not improving by 4 months.
Practical tips
- University/work — explain illness; phased return beats crashing and relapsing
- Do not kiss or share utensils while acutely infectious
- Avoid alcohol until liver tests normal if jaundice occurred
- Sleep — fatigue is physiological, not laziness
Glandular fever is miserable but almost always self-limiting in healthy young people. Patience with fatigue, avoiding contact sport, and not taking inappropriate antibiotics are the keys to safe recovery.
Common questions
- How long does glandular fever last?
- Acute symptoms — sore throat, fever, swollen glands — usually improve over 2 to 4 weeks. Fatigue and tiredness often persist for weeks to months — sometimes up to 6 months — even after other symptoms resolve. Gradual return to normal activity is advised; rushing back often worsens fatigue.
- Is glandular fever the same as mono?
- Yes — infectious mononucleosis (mono) is the medical name; glandular fever is the common UK term. Both refer to the same illness, usually caused by Epstein-Barr virus.
- How do you catch glandular fever?
- Mainly through saliva — kissing (hence "kissing disease"), sharing cups or utensils, or coughs and sneezes. EBV is very common — many people are infected in childhood with mild or no symptoms. Teenagers and young adults more often get full glandular fever symptoms.
- Can you get glandular fever twice?
- Very rarely — EBV usually causes lifelong immunity after first infection. Fatigue relapses months later are common but are not reinfection — post-viral fatigue is part of recovery. Other viruses can cause similar illness.
- Why should you avoid sport with glandular fever?
- EBV enlarges the spleen — contact to the abdomen during sport can cause splenic rupture, a life-threatening bleed. Avoid contact sports, heavy lifting, and strenuous exercise for at least 4 weeks, longer if the spleen is still enlarged on examination.
- What is the glandular fever rash?
- A widespread red rash can occur if amoxicillin or ampicillin is given for presumed bacterial tonsillitis before EBV is diagnosed — not an allergic reaction in the usual sense but a characteristic interaction. Tell any doctor you have or may have glandular fever before taking antibiotics.
- Can glandular fever cause liver problems?
- Mild liver inflammation is common — slightly raised liver enzymes, sometimes mild jaundice. Usually resolves with recovery. Avoid alcohol while unwell. Severe hepatitis is rare.
- When can I return to school or work?
- When fever has gone and you feel able — often after 1 to 2 weeks for desk work or study. Physical jobs and sport need longer. Fatigue may limit full capacity for weeks — phased return helps.