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Can you get a fever with hay fever?

Can you get a fever with hay fever?

Navin Khosla NowPatientGreen tick
Created on 16 Jul 2024
Updated on 16 Jul 2024

Allergies, particularly seasonal hay fever, are common disorders affecting millions of people worldwide. Many people assume that allergies, with their characteristic symptoms like sneezing, congestion, a runny nose and itchy eyes, must also cause fever, but contrary to this belief, allergies themselves do not directly lead to a fever. In this comprehensive article, we’ll explore the relationship between allergies and fever, dispel common misconceptions, and provide insights on when to seek medical attention for fever-like symptoms.

Understanding allergies

Allergies, also known as allergic rhinitis or hay fever, are an immune system response to harmless environmental substances called allergens. When the body encounters these allergens, it releases chemicals like histamine, triggering allergy symptoms. Common allergens include pollen, dust mites, pet dander, cockroaches and mold spores.

Seasonal vs. year-round allergies

Allergies can be seasonal, occurring at specific times of the year when certain plants are pollinating, or they can be perennial, persisting throughout the year due to indoor allergens. Seasonal allergies are often associated with tree, grass, or ragweed pollen, while year-round allergies are typically triggered by dust mites, animal dander, or mold.

Allergy symptoms

The common symptoms of allergies include:

  • Runny, itchy nose
  • Sneezing
  • Stuffy nose
  • Sinus pressure
  • Itchy, watery eyes
  • Itchy or sore throat
  • Cough

While these symptoms can be quite bothersome, they do not directly cause a fever.

Allergies vs. Fever

Fever is a common sign of an infection, but it is not a symptom of allergies. Allergies are an overreaction of the immune system to harmless substances, while fevers are the body’s response to fighting off bacteria or viruses.

What causes fever?

Fever is typically triggered by substances called pyrogens that reset the body’s thermostat to a higher temperature. This happens when the immune system detects an infection and sends white blood cells to fight it off. The increased body temperature makes it harder for the invading pathogens to survive.

Allergies don’t cause fever

Unlike infections, allergic reactions do not involve the release of pyrogens or a rise in body temperature. Allergy symptoms occur when the immune system releases histamine and other chemicals in response to allergens, and not in an attempt to fight off an infection. Therefore, allergies alone cannot directly cause a fever.

When allergies and fever coincide

While allergies do not directly lead to fever, there can be some connection between the two conditions. Here’s how they may occur at the same time:

Weakened immune system

Prolonged allergy symptoms can weaken the immune system, making a person more prone to viral or bacterial infections. If an allergy sufferer develops a common cold, flu, or sinus infection on top of their allergy symptoms, they may experience a fever along with their other allergy-like symptoms.

Sinus infections

One of the most common complications of allergies is sinus infections or sinusitis. Allergy-induced nasal and sinus inflammation can trap mucus, creating an ideal environment for bacteria or viruses to thrive. A sinus infection often presents with fever, along side thick nasal discharge, facial pain, and headaches.

Asthma flare-ups

For individuals with asthma, severe allergy symptoms can trigger asthma attacks. While asthma itself does not cause fever, the underlying inflammation and respiratory distress may lead to a fever.

When to seek medical attention

While allergies alone do not cause fever, there are certain situations where you should seek medical care if you have a fever:

  • Fever that lasts more than a few days and doesn’t improve with rest and over-the-counter medications
  • Fever accompanied by severe headache, neck stiffness, or changes in vision
  • Fever with difficulty breathing, chest pain, or severe sinus pain
  • Fever in young children, especially infants, as they are more susceptible to serious infections

In these cases, it’s crucial to see a doctor to rule out any underlying infections or other medical conditions that may be causing the fever.

Managing allergies and fever

If you have allergies and develop a fever, the best course of action is to:

  • Identify the cause: Determine whether the fever is due to an allergy-related complication, such as a sinus infection, or a separate viral/bacterial infection
  • Treat the fever: If the fever is not caused by an infection, OTC (over-the-counter) pain relievers are treatment options that can help manage the fever
  • Address the allergies: Continue using your prescribed allergy medications, such as antihistamines, nasal corticosteroids, eye drops or decongestants, to alleviate your allergy symptoms. A person with severe allergies may benefit from immunotherapy or allergy shots
  • Seek medical attention: If the fever persists or is accompanied by concerning symptoms, consult your healthcare provider for proper diagnosis and treatment. Working with your allergist will help to pinpoint your specific allergens

By understanding the distinction between allergies and fever, you can better manage your symptoms and seek the appropriate medical care when needed.


While allergies and fever may sometimes appear at the same time, the two conditions are not directly linked. Allergies themselves do not cause a fever, as they are the result of an immune system overreaction to harmless substances, rather than an infection-fighting response. However, prolonged allergy symptoms can weaken the immune system and increase the risk of developing secondary infections, which may then lead to a fever. Remember, if you experience a persistent or concerning fever, it’s always best to consult with a healthcare provider for proper diagnosis and treatment.


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NowPatient has taken all reasonable steps to ensure that all material is factually accurate, complete, and current. However, the knowledge and experience of a qualified healthcare professional should always be sought after instead of using the information on this page. Before taking any drug, you should always speak to your doctor or another qualified healthcare provider.

The information provided here about medications is subject to change and is not meant to include all uses, precautions, warnings, directions, drug interactions, allergic reactions, or negative effects. The absence of warnings or other information for a particular medication does not imply that the medication or medication combination is appropriate for all patients or for all possible purposes.

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