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Dr. Chrysoula I. Liakou MD, PhD
- Treated online: Yes, usually. Glandular fever is assessed by video with a blood test arranged where it helps; care is symptom relief, spleen safety and recovery advice, because antibiotics do not help a viral infection.
- What it is: infectious mononucleosis, caused in about 9 in 10 cases by the Epstein-Barr virus, spread mainly through saliva; most common between 15 and 25, and most adults carry the virus by 40 without ever knowing.
- How long: the sore throat and fever usually settle within 2 to 3 weeks; fatigue commonly lingers for several weeks and in some people a few months.
- The amoxicillin rash: amoxicillin and ampicillin trigger a widespread, blotchy, itchy rash in most people who actually have glandular fever, which is one reason a careful diagnosis matters.
- Spleen safety: contact sports, heavy lifting and vigorous exercise are avoided for at least 3 to 4 weeks while the spleen may be enlarged, to lower the small risk of rupture.
- Emergency: call 112 for sudden severe pain in the upper left abdomen or the tip of the left shoulder, difficulty breathing, or being unable to swallow your own saliva.
Glandular fever occasionally causes complications that need in-person care now. Sudden severe pain in the upper left side of the abdomen or the tip of the left shoulder can signal a problem with the spleen and is an emergency. Difficulty breathing, noisy breathing, drooling, or being unable to swallow your own saliva because of swollen tonsils also needs urgent assessment, as does being unable to keep any fluids down. If you have sudden severe abdominal pain or struggle to breathe, call 112.
Can an online doctor treat glandular fever?
Glandular fever is caused by a virus, so there is no antibiotic or antiviral that cures it, and care is about managing symptoms safely while the body recovers. A video consultation can confirm the likely diagnosis, arrange a blood test to be sure, and give you clear advice on rest, pain relief and protecting your spleen. Severe swelling that threatens breathing or swallowing needs in-person care.
Because glandular fever is diagnosed from the pattern of symptoms and a blood test rather than a physical examination, it suits video assessment well. The doctor takes the history, looks at your throat and glands on camera, and, crucially, tells you honestly what the weeks ahead usually look like, which is the part most people are never properly warned about.
How an online consultation helps with glandular fever
- The right diagnosis, not a wrong prescription: glandular fever is frequently mistaken for bacterial tonsillitis and treated with antibiotics that do nothing and can trigger a rash. The doctor separates the two and arranges the blood test that settles it.
- Honest recovery expectations: you are told plainly that the deep fatigue can last several weeks, sometimes longer, so you can plan work, study and exercise around a realistic timeline rather than a hopeful one.
- Spleen safety advice: the doctor explains why contact sports and heavy lifting are paused while the spleen may be enlarged, and when it is safe to return, which is genuinely important and often missed.
- A clear safety net: you leave knowing the specific warning signs (severe abdominal pain, breathing or swallowing trouble, dehydration) that mean urgent in-person care rather than waiting it out.
What is glandular fever?
Glandular fever, also called infectious mononucleosis or simply mono, is an infection most often caused by the Epstein-Barr virus (EBV).[1] It is common in teenagers and young adults, though it can occur at any age. The virus spreads through saliva, which is why it has earned the nickname the kissing disease, but it also passes on shared cups, cutlery, toothbrushes and through coughs and sneezes. Many people are infected with EBV in childhood with few or no symptoms; when infection happens later, the illness tends to be more pronounced.
The classic combination is a severe sore throat, a high temperature, and swollen, tender glands in the neck and elsewhere, together with a level of tiredness that is out of proportion to an ordinary throat infection. Some people also notice a swollen spleen, mild yellowing of the skin, puffy eyes or a rash. The sore throat and fever usually ease within two to three weeks, but the fatigue is the symptom that lingers.[1]
Why antibiotics do not help, and the amoxicillin rash
Because glandular fever is viral, antibiotics have no effect on it whatsoever.[1] This matters for more than stewardship. Glandular fever looks a great deal like bacterial tonsillitis, so it is often treated with antibiotics before the diagnosis is clear, and one group in particular causes a problem: amoxicillin and ampicillin (aminopenicillins) frequently trigger a widespread, blotchy, itchy rash in people who actually have glandular fever.[1][4] This rash is not usually a true, lasting penicillin allergy, but it is unpleasant and alarming, and it is a well-recognised clue that the underlying illness was glandular fever all along. Sorting out whether a sore throat is likely glandular fever, likely bacterial tonsillitis, or an ordinary viral sore throat is exactly the kind of decision a careful consultation is for, and it is why unnecessary antibiotics for a sore throat are worth avoiding. Antibiotics are only prescribed when there are genuine signs of a bacterial infection, and they do not work against viruses.[3]
How long does glandular fever last?
The acute phase, the sore throat, fever and worst of the swollen glands, usually improves within two to three weeks. The tiredness is different. It is normal for fatigue to persist for several weeks after the other symptoms have gone, and in some people a lower level of tiredness lingers for a few months before energy fully returns.[2] This is a recognised part of the illness, not a sign that something is wrong, but it is also why glandular fever is so disruptive to exams, work and training, and why pacing yourself matters.
Recovery is helped by the simple basics: rest without forcing yourself back too soon, regular fluids, and paracetamol or ibuprofen for the fever and sore throat. There is no tonic, supplement or medicine that speeds up clearance of the virus, and pushing hard through the fatigue tends to set recovery back rather than forward.[5] A phased return to normal activity, adding a little at a time and easing off if the tiredness flares, works better than an all-or-nothing approach.
Protecting your spleen: why contact sports wait
Glandular fever often enlarges the spleen, an organ tucked under the left side of the ribcage. An enlarged spleen is more fragile, and a blow to the abdomen or a sudden strain can, rarely, cause it to rupture, which is a life-threatening emergency. For this reason, contact and collision sports, heavy lifting and vigorous exercise are avoided in the early weeks of the illness while the spleen may be enlarged, commonly for at least the first three to four weeks and sometimes longer depending on how you recover.[1] Your doctor advises on timing for your situation. Sudden severe pain in the upper left abdomen, or pain referred to the tip of the left shoulder, needs emergency assessment, as it can be the first sign of a splenic problem. This single piece of advice is one of the most important reasons to have glandular fever properly assessed rather than self-diagnosed.
How doctors decide if glandular fever is safe to manage online
Whether glandular fever can be managed with online care depends on how severe the symptoms are and whether any complication is developing. The table below shows how doctors sort the presentations.
Swipe sideways to compare →
| Glandular fever presentation | Likely first step | Suitable for online care? | When referral or in-person care is needed |
|---|---|---|---|
| Typical illness, sore throat and fatigue, still able to drink and swallow | Supportive care, spleen advice, and a blood test to confirm | Usually yes | If symptoms worsen or a complication develops |
| Diagnosis uncertain (could be strep or glandular fever) | Assessment plus a blood test to distinguish them[1] | Yes, for assessment and test referral | In person for the blood test and any throat swab |
| Very swollen tonsils, struggling to swallow saliva or breathe | Urgent in-person assessment of the airway | No | Same-day: airway swelling can be an emergency |
| Prolonged fatigue beyond the expected weeks | Review to check recovery and exclude other causes | Yes | In person if fatigue is not settling or new symptoms appear |
| Severe upper-left abdominal or left shoulder-tip pain | Emergency care for a possible spleen problem | No | Call 112 immediately |
Not sure which row is you? A doctor can tell you in one consultation.
See available times →What the doctor checks in an online glandular fever consultation
The assessment is a structured history plus a careful look on camera, aimed at confirming the diagnosis and ruling out complications. In a glandular fever consultation the doctor will typically check:
- The symptom pattern: how long you have had the sore throat, fever and swollen glands, and how the fatigue compares with an ordinary infection.
- Your throat and glands on camera: the size and appearance of the tonsils, any coating, and swollen glands in the neck.
- Swallowing and breathing: whether swollen tonsils are making it hard to swallow saliva or breathe, which changes the urgency entirely.
- Signs pointing to the spleen or liver: abdominal discomfort, and any yellowing of the skin or eyes.
- Whether a blood test is needed: to confirm glandular fever and, where relevant, to check the liver and blood counts.
- Any antibiotics already taken: especially amoxicillin or ampicillin, and whether a rash followed, which is a strong clue.
- Your activities: contact sports, training or physical work that need pausing while the spleen may be enlarged.
When glandular fever is treated online, and when you need in-person care
Treated online: the typical illness in someone who is unwell but able to drink and swallow, where the job is to confirm the diagnosis, manage symptoms, give spleen and recovery advice, and set a clear safety net; uncertain sore throats where a blood test will separate glandular fever from a bacterial cause; and lingering fatigue that needs review to check recovery is on track.
In-person care: very swollen tonsils that threaten swallowing or breathing, which need same-day in-person assessment; any sign of a spleen problem, which is an emergency;[1] marked yellowing of the skin or eyes, or being unable to stay hydrated; and fatigue that is not resolving over an unusually long time, which needs in-person review to look for other causes. In those cases the consultation gets you to the right care quickly. Glandular fever is one of several overlapping cold and flu illnesses the doctors assess online, and it is easily confused with a high fever from other infections.
When to get in-person care
Get urgent in-person care if swollen tonsils make it hard to swallow saliva or breathe, if you cannot keep fluids down, or if the skin or whites of the eyes turn yellow. Call 112 immediately for sudden severe pain in the upper left side of the abdomen or the tip of the left shoulder, which can be a sign of a ruptured spleen, or for any serious difficulty breathing. A ruptured spleen is rare but life-threatening, and it is the reason contact sports and heavy lifting are paused during recovery.
Is glandular fever contagious?
Yes, but less dramatically than its nickname suggests. The kissing disease spreads through saliva, mainly kissing and shared drinks and cutlery, and the incubation runs four to seven weeks, so nobody can ever say exactly who gave it to whom.
How long are you infectious? The virus can be shed for months after recovery, which is why strict isolation is pointless and not recommended; sensible habits, no shared glasses or kissing while acutely ill, are the honest middle ground.
What it is often mistaken for: severe tonsillitis; the differences and the timeline are on this page, and tonsillitis has its own contagion answer.
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Frequently asked questions about glandular fever
What is glandular fever?
Glandular fever, also called infectious mononucleosis or mono, is a viral infection usually caused by the Epstein-Barr virus. It brings a severe sore throat, swollen glands in the neck, fever, headache and a deep tiredness that can outlast the other symptoms by weeks. It is most common between 15 and 25, it is not treatable with antibiotics, and nearly everyone recovers fully.
What are the symptoms of glandular fever?
Glandular fever typically causes a very sore throat with swollen, white-coated tonsils, swollen glands in the neck and sometimes the armpits and groin, a fever, headache, aching muscles, loss of appetite and profound tiredness. Some people develop a puffy face, a faint rash, a tender upper left abdomen from an enlarged spleen, or mild jaundice. Symptoms build over several days.
How do you catch glandular fever, and is it contagious?
Glandular fever spreads mainly through saliva, which is why it is nicknamed the kissing disease, and also through shared cups, cutlery and toothbrushes, and through coughs and sneezes. The virus is contagious from before symptoms start and for weeks after, and people shed it intermittently for months. It is far less contagious than a cold, so close contacts rarely need to isolate.
How long does glandular fever last?
The sore throat and fever of glandular fever usually settle within two to three weeks, but fatigue commonly lingers for several weeks afterwards, and in some people a lower level of tiredness lasts a few months. This is a normal part of the illness rather than a complication, and recovery is steady if rest and activity are paced.
Why do antibiotics not work for glandular fever?
Glandular fever is caused by a virus, and antibiotics act only on bacteria, so they make no difference to it. Amoxicillin and ampicillin can also trigger a widespread rash in people with glandular fever, which is one reason a careful diagnosis matters before any antibiotic is given for a sore throat; a bacterial tonsillitis on top is treated separately when a test shows it.
Do I need a blood test to diagnose glandular fever?
Often, yes. The symptoms strongly suggest glandular fever, but a blood test confirms it and can distinguish it from a bacterial throat infection. The doctor can advise whether a test is worthwhile in your case and arrange it, along with a liver test where jaundice or tenderness suggests the liver is involved.
Is it glandular fever or tonsillitis?
Bacterial tonsillitis brings a sore throat, fever and swollen tonsils over a day or two and settles within a week, with or without antibiotics. Glandular fever builds more slowly, lasts longer, and adds swollen glands beyond the neck, exhaustion out of proportion to the throat, and sometimes a puffy face, rash or tender spleen. A blood test separates the two when the picture is unclear.
How is glandular fever treated, and what helps at home?
There is no cure for glandular fever, so treatment is symptom relief: paracetamol or ibuprofen for the throat, fever and aches, plenty of fluids, gargling with warm salty water, soft food if swallowing hurts, and rest balanced with gentle activity as energy returns. A short steroid course is used only for tonsils so swollen they threaten breathing or swallowing, which is in-person care.
When can I play sport again after glandular fever?
Contact and collision sports, heavy lifting and vigorous exercise are avoided while the spleen may be enlarged, commonly for at least the first three to four weeks of glandular fever and sometimes longer. This lowers the small risk of a spleen injury. Your doctor advises when it is safe to return, building up gradually rather than going straight back to full training.
Can you get glandular fever twice?
Almost never. After glandular fever the Epstein-Barr virus stays in the body for life, usually silently, and the immune system keeps it in check, so a second bout of the illness is very rare. Tiredness or sore throats that return months later are far more likely to have another cause, which is worth assessing rather than attributing to a relapse.
Is glandular fever different in adults over 30 or in pregnancy?
In adults over 30, glandular fever is less common and often milder in the throat but with more prolonged fever, tiredness and liver involvement, so blood tests are more often needed. In pregnancy it is managed with rest, fluids and paracetamol, and it does not harm the baby; the doctor coordinates with your maternity team if the fever is high or you cannot keep fluids down.
How can glandular fever be prevented?
There is no vaccine for glandular fever. The practical measures are not sharing cups, bottles, cutlery or toothbrushes, avoiding kissing someone who has it, washing hands after coughs and sneezes, and keeping the person who is ill away from shared drinks until they are well. Most adults have already met the virus and are immune without knowing it.
- Glandular fever (infectious mononucleosis), NICE CKS, Clinical Knowledge Summaries, reviewed 2024.
- Glandular fever, HSE, Health Service Executive (Ireland), reviewed 2024.
- Antimicrobial resistance, ECDC, European Centre for Disease Prevention and Control, 2023.
- Infectious mononucleosis, DermNet, DermNet New Zealand Trust, accessed August 2026.
- Steroids for short-term symptom control in infectious mononucleosis (glandular fever), Cochrane Review, Cochrane, 2015.
- Glandular fever, NHS, National Health Service (UK), accessed October 2026.
This page is for information only and is not a substitute for a medical consultation. Guideline links are provided for transparency; treatment decisions are made with your doctor.
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