How Long Does Glandular Fever Last and When Should You Get Medical Help?

Glandular fever can knock you off your feet for weeks. It is one of the more exhausting viral infections a young person can get, and one of the most common questions people ask is how long it will last. Whether you are a student who has missed lectures, a young worker trying to manage sick leave, or a parent watching your teenager struggle to get off the couch, understanding the timeline matters.

This article covers how long glandular fever typically lasts, what to expect at each stage of recovery, which symptoms need urgent attention, and when it is appropriate to return to work, study, or sport.

If you are feeling unwell and unsure whether your symptoms are normal, an telehealth consultation online can help assess them and guide you on the next steps, without needing to visit a clinic.

Quick Answer: How Long Does Glandular Fever Last?

Most people with glandular fever start to feel noticeably better within two to four weeks. The sore throat and fever often settle within one to two weeks. Fatigue, however, tends to persist much longer, lasting several weeks to a few months after other symptoms have resolved.

• Sore throat and fever: often resolve within one to two weeks
• Swollen glands: may take two to four weeks to reduce
• Fatigue: can last four to eight weeks, and sometimes longer
• Some people experience lingering tiredness for several months
• Seek urgent care if you have severe abdominal pain, trouble breathing, or signs of dehydration

What Is Glandular Fever and Why Can It Drag On?

Glandular fever is the common name for infectious mononucleosis. It is caused by the Epstein-Barr virus (EBV), a member of the herpes virus family. EBV is very common. Most people are infected at some point in their lives, but when it strikes during the teenage or young adult years, it tends to cause a more noticeable illness.

The virus spreads through saliva, which is why it is sometimes called the kissing disease. You can also pick it up by sharing drinks, cutlery, or personal items with someone who is unwell.

Fatigue can linger because the immune system takes time to recover after fighting off the virus. EBV also affects the lymphatic system and can temporarily enlarge the spleen. Even after the acute phase passes, energy levels can remain low while the body continues to heal.

• Most common in teenagers and young adults aged 15 to 30
• Spreads through saliva and close personal contact
• The incubation period is typically four to six weeks after exposure

Typical Timeline: A Week-by-Week Guide

Week 1 to 2: Peak Symptoms

The first one to two weeks are usually the worst. Most people feel severely fatigued from the start. The sore throat can be very painful, sometimes worse than a standard strep throat. Swollen neck lymph nodes are common and easy to feel.

• Extreme tiredness that makes normal activity difficult
• Severe sore throat, sometimes with white patches on the tonsils
• Fever, often between 38 and 40 degrees Celsius
• Swollen glands in the neck, armpits, or groin
• Difficulty swallowing, reduced appetite, and risk of dehydration

Week 2 to 4: Symptoms Start to Ease

The sore throat and fever usually settle during this period. Swollen glands slowly reduce. Most people can manage light activity and return to basic daily tasks, though energy is still well below normal.

• Throat pain gradually improves, and eating becomes easier
• Fever typically resolves within the first two weeks
• Fatigue persists, and rest remains important during this stage

After 4 Weeks: Why Some People Still Feel Tired

Many people find that physical and mental energy takes the longest to return. Reduced stamina, difficulty concentrating, and persistent tiredness are all common, even after the main symptoms have resolved. This is sometimes called post-viral fatigue.

If fatigue is not improving after four to six weeks, or if it seems to be getting worse rather than better, it is worth speaking with a clinician for a review.

Recovery timelines can vary from person to person. If your symptoms are lasting longer than expected or you need advice about returning to work, study, or sport, an online doctor can review your situation and provide personalised guidance.

Symptoms That Fit Glandular Fever (and Symptoms That Suggest Something Else)

Symptoms can vary, and not everyone gets the same pattern. Some people have a very pronounced sore throat. Others find fatigue is the dominant problem. A mild skin rash is also possible in some cases.

• Severe fatigue that does not improve with rest
• Sore throat or tonsillitis
• Fever
• Swollen lymph nodes in the neck, armpits, or groin
• Headache and body aches
• Skin rash (in some cases, particularly if certain antibiotics are taken)

These symptoms can overlap with other infections, including strep throat, cytomegalovirus infection, or early HIV. A medical review can help clarify the cause.

Consider a medical review if you also experience:

• A very high fever that does not settle after a few days
• Severe one-sided throat pain that worsens rapidly
• Shortness of breath or difficulty breathing
• Symptoms that keep escalating rather than settling after the first week

Because glandular fever symptoms can overlap with those of other infections, a medical review can help confirm whether your symptoms are consistent with glandular fever or if further tests are needed.

When Should You Get Medical Help?

Seek Urgent Care Now If You Have Any of These

Some symptoms require immediate attention. Do not wait for a routine appointment if you experience any of the following.

• Severe pain in the left upper abdomen or left shoulder tip (this may suggest a problem with the spleen)
• Trouble breathing or swallowing due to severe throat swelling
• Signs of dehydration: very dark urine, dizziness, or inability to keep fluids down
• Yellowing of the skin or whites of the eyes (jaundice)
• Chest pain, fainting, or sudden severe weakness

Book a Medical Review If Symptoms Are Not Improving

Not every situation requires emergency care, but some situations do warrant a medical review. The following are worth discussing with a doctor.

• Fatigue that is not improving after three to four weeks
• Persistent fever beyond the first week or two
• Symptoms that seemed to improve but have returned or worsened
• Need for medical documentation for work, university, or school absence

If you are experiencing ongoing fatigue, worsening symptoms, or need documentation for work or study, an online GP consultation can provide medical advice, arrange referrals or blood tests if appropriate, and issue a medical certificate when clinically indicated.

Tests and Diagnosis: What a Clinician May Check

Glandular fever is often diagnosed based on symptoms and clinical assessment. Blood tests can help confirm the diagnosis or rule out other causes, though the timing of testing matters because results may be negative in the very early stages.

• Full blood count (FBC): may show an elevated white cell count and atypical lymphocytes
• Monospot test: checks for heterophile antibodies, though it can be negative early in the illness
• EBV-specific antibody tests: can help confirm the diagnosis when the monospot is negative
• Liver function tests: may be ordered if liver inflammation is suspected

A clinician can explain what your results mean and whether any follow-up monitoring is needed. This is especially relevant if fatigue continues well beyond the expected recovery period.

If blood tests or follow-up monitoring are required, an online doctor can organise pathology referrals and review your results, helping you understand what they mean and what to do next.

Recovery Tips That Actually Help

There is no specific antiviral treatment for glandular fever. Recovery is largely about supporting your body while it does the work.

Rest: Pace yourself and avoid pushing through heavy fatigue. Short periods of gentle activity are fine when tolerated, but crashing repeatedly can slow recovery.

Fluids: Stay hydrated, especially if your throat is too sore to eat or drink much. Icy poles and cold drinks can also help soothe the throat.

Pain and fever relief: Paracetamol or ibuprofen can help manage fever and throat pain. Always follow label directions. Aspirin should not be given to children.

Food: Soft foods are easier to manage when swallowing is painful. Soups, yoghurt, and smoothies can help maintain nutrition.

Work and study: A graded return is usually better than going straight back to a full load. Reducing late nights and stress early on can help prevent setbacks.

Recovery is often gradual. Some days will feel better than others, and that is completely normal.

Returning to Work, the Gym, and Sport: Spleen Safety

One of the more serious, though uncommon, complications of glandular fever is spleen enlargement. During the illness, the spleen may enlarge, making it more prone to injury. A significant impact on the abdomen during this time could, in rare cases, cause a rupture.

• Avoid contact sports, heavy lifting, and vigorous exercise during the acute phase and early recovery
• A return to sport should be gradual and ideally guided by a clinician
• If you develop sudden or worsening abdominal pain during or after recovery, seek medical assessment promptly
• Most people can return to normal activity once symptoms have substantially resolved and a clinician advises it is appropriate

If you are unsure when it is safe to return to work, university, or physical activity, an online GP can assess your recovery and provide advice or clearance based on your symptoms.

How Long Are You Contagious?

EBV spreads through saliva. You can pass it on to others through close contact, kissing, or sharing personal items. The virus can remain in saliva for weeks, even after you start feeling better, though the risk of passing it on is generally highest during the acute phase.

• Avoid sharing cups, cutlery, or water bottles while unwell
• Do not share vapes, lip balm, or toothbrushes
• Wash your hands regularly, especially if you are caring for someone who is unwell

If someone in your household becomes unwell with similar symptoms, a medical review can help determine whether they may have the same infection.

FAQ’s:

Can glandular fever last longer than a month? 

Yes, it can. While most people feel significantly better within 2 to 4 weeks, fatigue often persists beyond 1 month. A small number of people experience symptoms that persist for several months. If your recovery is taking much longer than expected, a medical review is worth considering.

Why does fatigue last so long after glandular fever? 

The immune system takes time to recover after fighting off EBV. The body also needs to repair any temporary inflammation in the liver, lymph nodes, or spleen. Post-viral fatigue is a recognised response and does not mean something is seriously wrong, though persistent cases should be assessed.

When can I go back to work or university? 

This varies depending on how you are recovering. Many people can manage light duties or study within two to four weeks, but a graded return is usually better than going back full time straight away. A doctor can provide a medical certificate and guidance on timing based on your individual situation.

When can I return to the gym or sports? 

Contact sports and heavy exercise should be avoided during the acute phase and until spleen enlargement resolves. A clinician can advise when it is appropriate to return based on your symptoms and recovery progress. Returning too early carries a small but real risk.

Do I need antibiotics for glandular fever? 

No. Glandular fever is a viral infection, and antibiotics do not treat viruses. Antibiotics may be prescribed if a secondary bacterial infection develops, such as strep throat, but they will not shorten the course of glandular fever itself.

Should I get blood tests? What do they show? 

Blood tests can help confirm the diagnosis, particularly a full blood count and EBV antibody tests. They can also check for liver involvement. Not every case requires testing, but a clinician may recommend it depending on your symptoms and how long you have been unwell.

When should I worry about my spleen? 

Seek urgent medical care if you develop sudden or severe pain in the left upper abdomen, especially if it extends to your left shoulder tip. This can indicate a spleen problem and requires immediate assessment. Avoid contact sports and heavy activity while recovering to reduce this risk.

If you still have questions after reading this guide, speaking with an online doctor can help clarify your symptoms, recovery expectations, and whether any further medical follow-up is needed.

A Final Word on Recovery

Most people with glandular fever do recover fully. The acute symptoms usually resolve within a few weeks, though fatigue can take longer. Being patient with your recovery and not rushing back to full activity often leads to a smoother outcome.

If you notice any of the red flag symptoms described in this article, seek care promptly. For everything else, rest, hydration, and time do most of the work.

Glandular fever recovery can be frustrating, especially when fatigue affects work, study, or daily life. If you need medical advice, follow-up care, blood test referrals, or a medical certificate, Telehealth Dr offers secure online GP consultations across Australia, allowing you to get the care you need from home.