Why Do I Feel Feverish Upon Waking? (31 Morning Fever Causes)

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This article has been written and researched by Ana Luiza – a sleep scientist, psychobiologist, and biotechnologist, (Ph.D.) – to ensure the highest content quality and factual accuracy.

A fever is when your body temperature is greater than 100.4 F or 38◦C.

A fever is a very unspecific symptom that can manifest in several conditions – which can often make it quite difficult to pinpoint exactly why you are waking up with a fever in the morning without a medical examination.

So what are the most common causes of morning fever?

The most likely causes of morning fever are the influenza virus, pharyngitis, sinusitis, an ear infection, gastroenteritis, food poisoning, teething (in infants), or a reaction to medication. However, it’s recommended that you consult a doctor for a precise diagnosis.

The rest of this article lists 31 causes of morning fever and includes tips for prevention and treatment where appropriate.

However, this is just a guide and should not be interpreted as medical advice – always consult with a doctor or a medical professional for the best guidance because a persistent fever can indicate a serious condition.

Related: check out these 9 ways to sleep better with a fever here.

31 Causes of Morning Fever

Below are 31 potential causes of morning fever:

1: Pharyngitis

Pharyngitis is the inflammation of the pharynx, which results in what people call a sore throat.

A sore throat is considered a symptom rather than a condition.


Common viruses and bacteria can cause pharyngitis – such as the flu virus, coronavirus, mononucleosis virus, and Streptococcus bacteria.

Pharyngitis can also result from fungal infections – especially in immunocompromised people – and/or through long-lasting antibiotic or anti-inflammatory medication use.

Other causes of sore throat are allergies, chronic mouth breathing, excessive voice use, and stomach acid reflux.


The symptoms of pharyngitis are:

  • Sore throat.
  • Dry or scratchy throat.
  • Pain when swallowing or speaking.


If you have a sore throat with a fever you should seek medical help from your doctor or the emergency room if symptoms are severe.

A doctor will examine your throat and ask about your other symptoms to reach a diagnosis.

After finding the possible cause for your sore throat, he/she will indicate a proper treatment.

Sometimes, the infection goes away on its own.

The treatment can include:

  • Pain relievers.
  • Drinking a lot of fluid.
  • Antibiotics in the case of bacterial pharyngitis.
  • Antifungal medications when caused by a fungus.

2: Influenza

Influenza is a respiratory infection, which is caused by the influenza virus.

This virus is commonly associated with seasonal epidemics (mainly during fall and winter).

The influenza virus caused pandemics like the H1N1 in 2009.

The virus spread through airborne droplets and person-to-person contact.


The influenza virus can stay silent for up to 4 days.

The symptoms of influenza resemble a common cold, including:

  • Headache.
  • Fever.
  • Chills.
  • Cough.
  • Fatigue.
  • Aches and pains.

Certain people are more at risk of developing complications due to influenza infection, especially children, older people (> 65 years old), and people with chronic medical conditions.


If you have the symptoms listed above, it is essential to see a doctor.

Besides the clinical evaluation, you may also need to do a molecular test, an X-ray, or pulse oximetry.

Most people will fully recover in about 1-2 weeks.

The treatment can involve pain killers, anti-inflammatory, and antiviral medication.

Sometimes, antibiotics can be prescribed to control secondary pulmonary infections.

Measures to prevent Influenza infection are:

  • Vaccination.
  • Avoid contact with sick people.
  • Avoid crowded places.
  • Wash your hands frequently.

3: Avian Flu

The type A influenza virus causes avian flu.

These viruses are naturally found in aquatic birds and can infect poultry and other animals.

Infections in humans occasionally occur.

The symptoms, transmission, treatment, and prevention measures are similar to what we described for the influenza virus.

4: Sinusitis

When you have acute sinusitis, the spaces inside your nose (sinuses) become inflamed.

This causes drainage blockage and mucus build-up.


Sinusitis can be associated with a viral (common cold) or bacterial infection. 


Some common symptoms of sinusitis are:

  • Thick, yellow, or greenish discharge from the nose or the back of the throat.
  • Pain around the eyes, cheeks, nose, or forehead.
  • Headache.
  • Stuffy nose.

Other symptoms can occur, like fatigue and fever. 


Most cases of sinusitis resolve within a week.

See a doctor if:

  • You have symptoms that last for more than one week.
  • You have a persistent fever.
  • Your symptoms are recurrent.

In this case, the treatment can involve:

  • Saline nasal spray.
  • Anti-inflammatory medication.
  • Decongestants.
  • Pain relievers.


You can also take measures to prevent sinusitis, such as:

  • Using a humidifier.

5: Meningitis 

Meningitis is when the protective membranes covering your brain and spinal cord are inflamed.


Meningitis can result from a viral, fungal, or bacterial infection in the fluid that surrounds the brain.

Injuries, cancer, and certain drugs can also cause the disease.

The infection spreads from one person to another.

The way the disease spreads depends on the microorganism that caused the condition. 


Signs that you may have meningitis are:

  • Fever.
  • Headache.
  • Stiff neck.
  • Vomiting.
  • Nausea.
  • Light sensitivity.
  • Altered mental status.
  • Lack of energy.


While viral meningitis may resolve on its own, bacterial meningitis may become severe.

This is why you should seek medical attention to determine the cause of your symptoms and indicate a proper treatment.

The treatment depends on the cause, including antibiotics and other drugs to relieve the symptoms.

You can avoid getting meningitis by vaccinating against it. 

6: Pneumonia

Pneumonia is an infection that inflames the lungs’ air sacs and can be caused by viruses, fungi, or bacteria.

When you have pneumonia, the lungs become full of fluid or pus – causing a cough. 

Pneumonia seriousness varies – depending on the cause and the patient’s health conditions.


The following symptoms can be associated with pneumonia:

  • Chest pain when breathing or coughing.
  • Cough with pus or phlegm.
  • Fatigue.
  • Fever.
  • Chills.
  • Nausea, vomiting, or diarrhea.
  • Shortness of breath.


Pneumonia may be life-threatening, especially for young children, older people, and people with a weak immune system.

See a doctor if you’re in the high-risk group or if you have:

  • Difficulty breathing.
  • Chest pain.
  • Persistent fever or high fever.
  • Persistent cough.
  • Cough with pus.

The doctor can indicate the most suitable treatment, including antibiotics and other medications to relieve the symptoms.


To avoid getting pneumonia:

  • Get vaccinated.
  • Practice good hygiene.
  • Avoid smoking.
  • Avoid contact with sick people.

7: Ear Infection

Ear infections can be caused by a virus or bacteria and are very common in children. 

You may have an ear infection if you have the following symptoms:

  • Ear pain.
  • Fever.
  • Irritability.
  • Difficulty sleeping.


Seek medical attention, especially if you have:

  • Discharge coming from the ear.
  • Hearing loss.
  • High fever.
  • Worsening of symptoms.

The doctor will recommend an appropriate treatment based on a clinical exam.

The treatment may include antibiotics and pain relievers.

You should also rest and drink a lot of fluids to recover faster.

8: Gastroenteritis

Gastroenteritis is an infection of the digestive system.


Bacterial or viral infection can cause gastroenteritis (stomach flu).

It affects people of all ages, especially children.


Gastroenteritis can cause the following symptoms:

  • Diarrhea.
  • Nausea.
  • Vomiting.
  • Fever.
  • Loss of appetite.
  • Stomach pain.
  • Headache.


The symptoms usually go away in a few days.

But if symptoms persist, then you should seek medical help.

To ease your symptoms, you can:

  • Drink a lot of fluids.
  • Take pain relievers.
  • Eat healthy food.
  • Take anti-vomiting medication.

Signs you should see a doctor are:

  • Severe dehydration.
  • Persistent dizziness.
  • Loss of consciousness.
  • Bloody diarrhea.
  • High fever.
  • You have a severe health condition.

Sometimes, you may need to take antibiotics.

9: Osteomyelitis 

Osteomyelitis is bone inflammation caused by an infection.

A physician will recommend the appropriate treatment for your problem.

The treatment may include medication such as pain relievers and antibiotics.

More severe cases may require surgery.

You should also get some rest until you feel better.

10: Pericarditis

Pericarditis is the inflammation of the tissue that surrounds your heart (the pericardium). 


Pericarditis can happen due to viral, bacterial, or fungal infections.

Other reasons can be a heart attack, heart surgery, or the use of certain medications. 


The most prominent symptom of pericarditis is chest pain.

Other signs that can be present are:

  • Shortness of breath.
  • Fatigue.
  • Racing heart.
  • Fever.
  • Abdominal or leg swelling.


If you have chest pain, seek urgent medical treatment immediately.

The condition may clear up on its own, but it also may require more intense treatment. 

The treatment usually includes anti-inflammatory medication, pain relievers, and sometimes antibiotics or antifungals.

11: Roseola

Roseola is a childhood illness caused by the herpes virus. 


A child with roseola may have:

  • High fever.
  • Red and flat rash.
  • Runny nose.
  • Sore throat.
  • Upset stomach.


If a child is experiencing the symptoms above, see a doctor.

The treatment can involve anti-inflammatory drugs and medication to lower the fever.

Antiviral medication may be necessary.

12: Urinary Tract Infection (UTI)

UTI can develop due to bacterial infection in any part of the urinary system.


Possible symptoms of UTI are:

  • Strong urge to urinate.
  • Pain when urinating.
  • Passing frequent, small amounts of urine.
  • Changes in urine color, smell, or aspect.
  • Pelvic pain.


If you have the symptoms described above, seek medical attention.

If not treated properly, the bacteria can spread to your kidneys, which can be dangerous. 

The treatment usually involves antibiotics and pain killers.


To avoid getting UTI:

  • Drink a lot of fluid.
  • Drink cranberry juice.
  • Wipe from front to back for women.
  • Avoid using products in the genital areas.
  • Urinate after having sex.

13: Kidney Infection (Pyelonephritis)

Pyelonephritis is a kidney infection.

It usually starts in other parts of the urinary tract like the urethra or bladder.

It spreads to the kidneys if not treated.


Signs of a kidney infection include:

  • Fever.
  • Chills.
  • Back pain
  • Abdominal pain.
  • Pain when urinating.
  • Urge to urinate.
  • Nausea or vomiting.
  • Pus or blood in the urine.


If you suspect you have a kidney infection, go to a doctor immediately.

This type of infection can be dangerous and damage your kidneys. 

A kidney infection is treated similarly to a UTI.

The prevention measures are also the same. 

14: Coxsackievirus Infection

Also known as hand, foot, and mouth disease, this condition is associated with the Coxsackie virus, spreading from one sick person to another.


As the name says, people with this disease develop a rash on the hands, foot, and mouth.

Other possible symptoms are:

  • Fever.
  • Lack of appetite.
  • Runny nose.
  • Sore throat.


The symptoms usually resolve within five days. 

There is no specific treatment, only controlling the symptoms by using medication to lower the fever and keeping the body hydrated. 

15: Epiglottitis

Epiglottitis is the swelling of the upper airways, a condition that can cause asphyxia and death.

This can occur due to a viral infection like the Influenza virus or bacterial or fungal infection. 


  • Upper airway swelling.
  • Discomfort.
  • Agitation.
  • Fever.


Seek medical attention immediately.

A doctor will evaluate you and recommend treatment.

The most important thing is to make sure that the airway doesn’t close. 

Since it is a complicated condition, intubation or tracheotomy may be necessary.

The treatment also involves anti-inflammatory and antibiotics. 

16: Hepatitis

Hepatitis is the inflammation of the liver and organs that process vital nutrients.

Our body filters the blood and helps fight infections.

Hepatitis can occur due to viruses, alcohol use, toxins, and certain medications.

Examples of viral hepatitis are hepatitis A, B, and C.

Hepatitis A

Hepatitis A spreads from person to person through infected fecal material.

This can happen you eat contaminated food, for example. 

Hepatitis B

This type of hepatitis spreads mainly through sexual intercourse or contact with contaminated blood. 

Hepatitis C

Hepatitis C also spreads through contact with contaminated blood. 


The symptoms of hepatitis can include:

  • Fever.
  • Fatigue.
  • Loss of appetite.
  • Nausea.
  • Vomiting.
  • Abdominal pain.
  • Dark urine.
  • Light-colored stool.
  • Joint pain.
  • The skin can become yellow.


The best way to avoid getting hepatitis is by vaccinating.

Other preventive measures are:

  • Using a condom.
  • Avoiding needle sharing.
  • Hand hygiene before eating and after going to the toilet.
  • Washing vegetables and fruits before eating.


There is no recommended treatment for hepatitis A and B, only supportive therapy for the symptoms, as they appear.

It is also essential to monitor the liver’s health to check if it’s damaged.

Chronic hepatitis C can be treated with medication. 

17: Mononucleosis

Mononucleosis is a viral infection (Epstein-Barr virus) that spreads from one person to another through saliva.

It is more common in teens and children. 


The symptoms usually go away in a few weeks.

The treatment involves taking medication to lower the fever, pain, and inflammation.

It is also recommended to rest and stay hydrated.

Sometimes, warm salt water gargles may also help. 

18: Tuberculosis

Tuberculosis is an infection due to bacteria.

It spreads from one person to another via infected droplets from coughing or sneezing.

Besides the lungs, tuberculosis can also affect other parts of the body, such as the abdomen, bones, and nervous system.


Typical symptoms of tuberculosis include:

  • A persistent cough (more than three weeks), with phlegm.
  • Weight loss.
  • Night sweats.
  • Fever.
  • Swelling in the neck.
  • Tiredness.


Most cases resolve on their own, and the person does not show symptoms.

However, in some people, the infection can become symptomatic.

In this case, it is vital to seek medical help.

The treatment involves antibiotics, and it has a high chance of being cured.

The BCG vaccine offers protection against bacteria that cause tuberculosis.

19: Scarlet Fever

Scarlet fever or scarlatina is a bacterial infection that primarily affects children.

The bacteria spread from person to person via droplets expelled when someone coughs or sneezes.


People with this infection show a bright red rash that covers most of the body.

Other possible symptoms are:

  • Sore throat.
  • High fever.
  • Flushed face.
  • Strawberry tongue.
  • Difficulty swallowing.
  • Enlarged glands in the neck.
  • Nausea.
  • Vomiting.
  • Headache.


If your child has a high fever, a red rash, and swollen or tender glands in the neck, it is better to go to the doctor.

If untreated, the infection can spread to other body parts like the ears, lungs, kidneys, and blood.

The treatment involves antibiotics and other medications to control the symptoms, such as lowering the fever.

To prevent the infection, take the following measures:

  • Avoid contact with sick people.
  • Wash your hands frequently.
  • Cover your mouth and nose when coughing or sneezing.

20: Brain Infection (Encephalitis)

Encephalitis is inflammation in the brain due to viral or bacterial infection.

It causes flu-like symptoms, confusion, and sleepiness.

Encephalitis can be fatal and requires immediate medical care.

21: Chagas Disease

Chagas Disease is an infection caused by the parasite Trypanosoma cruzi and transmitted by the triatomine bug.

It is more common in South America, Central America, and Mexico.

22: Dengue Fever

Dengue fever is a disease spread through the bite of the infected Aedes mosquito.

It is more common in tropical areas.

There is no specific treatment.

It usually involves controlling the symptoms. 

23: Food Poisoning

High fever may indicate severe food poisoning which needs immediate medical attention. 

24: Sunburn

Fever can be associated with severe sunburn.

It can be resolved by applying cold compresses to the skin or taking cold baths.

Menthol, Camphor, and Aloe Vera creams or gels can also help. 

Click here to discover 13 ways to sleep better with sunburn.

25: Medication Reaction or Side-Effect

Talk to your doctor or pharmacist if you have a fever during treatment with any medication.

Some immunizations (vaccines) can also cause fever in some people. 

26: Depression, Stress, or Grief

Stress-related fever is an actual condition.

If this is happening to you, seek professional help.

You may need medication, psychotherapy, or a combination of both. 

If you are struggling with a breakup then see these 20 ways to get to sleep after a breakup.

27: Chronic Inflammatory Conditions

Crohn’s disease, rheumatoid arthritis, inflammatory bowel disease, and Lupus (systemic lupus erythematosus) can also cause fever in some people.

28: Cancer

Cancer is a group of more than 100 diseases with very different symptoms and treatments.

Fever may be a symptom of some types of cancer.

29: Surgery

Recent surgery can cause fever since your body is going through an intense inflammatory process to recover.

If persistent, talk to your doctor. 

30: Teething (Infants)

Teething can raise the baby’s body temperature.

Other signs are crying and irritation (more than usual), chewing objects, and drooling.

It is a good idea to give your baby something to massage their gums or chew, especially if it’s cool.

Sometimes, pain relievers can help.

Talk to your physician for more specific guidance.

31: Blood Clots

 When a blood clot breaks, it can enter the bloodstream and it can cause a fever.

This requires immediate medical attention. 

Conclusion: Seek Medical Advice

A fever is typically due to your body fighting an inflammatory stimuli.

It can be a virus, a bacteria, a fungus, or anything else that puts your immune system into action, raising your temperature.

Whilst some fevers may resolve on their own, the best course of action is to see a doctor as soon as possible, visit the emergency room in the more severe cases, or if a child, older individual, or vulnerable person is being affected.

Up next: click here to find out if lack of sleep can cause a fever.

Sources and References

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Medical Disclaimer

No part of this article or website provides medical advice – always consult with a qualified professional for the best treatment.

Image Attribution and Licencing

Main image: ‘Ill Woman With Cold and Flu Bad Symptoms’ by tommaso79 – used with permission under the terms of Canva’s One Design Use License Agreement.