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Allergies can cause symptoms that are very similar to a cold or flu, such as a runny nose, sore throat, or sneezing. However, allergies do not cause a fever.

Because each allergy has a different underlying cause, it is essential that a person receives the right diagnosis, so that they can get the best treatment.

In this article, we look at the relationship between allergies, colds, and flu. We also look at ways to treat the symptoms of an allergy.

Woman in bed with a fever wondering if allergies can cause a feverShare on Pinterest
Allergies do not cause a fever.

Some symptoms of allergies and colds are the same, such as a runny nose and sneezing. However, according to the National Institutes of Health, allergies should never cause fever.

Allergy symptoms occur when a person’s immune system overreacts and tries to fight off a harmless substance, such as pollen or pet dander. These substances then trigger an inflammatory immune system reaction.

Cold and flu symptoms are caused by viruses that affect the respiratory system. These viruses attack the body, causing the immune system to work overtime to keep the harmful virus at bay.

Symptoms associated with allergies include the following:

  • itching eyes
  • a runny nose
  • sneezing
  • stuffy nose

Allergies are more likely to occur seasonally, such as when molds release their spores or grasses, trees, and weeds release pollen that aids in plant fertilization.

A doctor who specializes in allergy treatments called an allergist can perform tests to see if a person is allergic to a specific substance. When the allergist performs a skin prick test, they expose the skin to common allergens to see if any trigger an allergic response.

They may also test the blood for the presence of specific allergy-related antibodies using ELISA (enzyme-linked immunosorbent assay) tests, or less commonly, RAST (radioallergosorbent) tests.

Symptoms associated with a cold or flu may include:

  • sneezing
  • coughing
  • a runny nose
  • congestion
  • fever
  • stomach pains
  • body aches

A fever is the body’s way of trying to increase the temperature to kill off bacteria or viruses. Because these germs are not present in an allergic reaction, a fever does not occur.

Differences between a cold, flu, and an allergy include:

  • Allergies tend to cause itchy, watery eyes. Colds and flu do not.
  • Allergies may last through a season (about 6 weeks) or go away when a person is no longer exposed to an allergen, such as an animal or mold spores. Colds tend to last 3 to 5 days, while the flu lasts 7 to 10 days.
  • Allergies do not usually cause body aches, pains, or the extreme exhaustion that the flu can.

An allergy is an inflammatory immune response to specific foods or something in the environment, known as an allergen. Colds and flu are caused by viruses or bacteria. Therefore, a cold or flu cannot cause an allergy.

Sometimes, allergies can lead to a sinus infection, which may develop into a fever. Sinus infections are the result of excess mucus and debris getting trapped in the air-filled sinus passages. However, the infection develops due to the bacteria or viruses present rather than the allergens.

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An allergy mask may help prevent a person breathing in allergens.

Knowing what a person is allergic to can help in treating the allergies. A person can be allergic to several allergens at once. Some of the key steps to reducing allergy symptoms include:

  • Reducing time spent outdoors when pollen, ragweed, or mold counts are very high. Websites such as the National Allergy Bureau offer daily updates on the status of these counts.
  • Avoiding raking leaves, mowing the lawn, or working in the garden while mold and pollen counts are high. These activities can unsettle potential allergens and make symptoms worse. Wearing an allergy mask over the face can prevent a person from breathing in allergens. Allergy masks can be purchased online.
  • Using air conditioning and keeping windows closed to keep pollen and other airborne allergens from coming into the home.
  • Applying a mite-proof bedding cover over a mattress to reduce the number of mites in the mattress.
  • Washing hands thoroughly and changing clothes after being outside or petting animals.
  • Taking over-the-counter medications to reduce allergy symptoms. Examples include decongestants and antihistamines. Many forms of allergy medication are available to buy online, including tablets, nasal sprays, and creams. Take these medications for a couple of weeks before allergy season to increase their effectiveness.

A person with severe allergies may benefit from immunotherapy. This approach involves injecting increasing amounts of allergens in the body to de-sensitize the body’s immune response. A doctor must prescribe these injections.

Seasonal allergy symptoms are unpleasant and share some similar symptoms as colds or flu. However, a fever or extreme fatigue are uncommon symptoms of allergies.

Treatments are available and limiting one’s exposure to the outdoors when allergen counts are at their highest can help to reduce the incidence of allergy symptoms.