Watery eyes, skin rash, runny nose, sneezing, and other allergy symptoms don’t cause fever. Do Allergies Cause Fever? However, some allergies can lead to inflammation in your sinuses and nose, which exposes you to sinus infection (sinusitis). If this happens, you’re likely to develop low-grade fever. In this case, the fever is caused by the infection, not allergy.

Fever vs Allergies

Generally, allergy symptoms include itchy eyes, sneezing, running nose, and stuffy nose. Fever isn’t an allergy. It is your body’s immune reaction to an infection. Whenever your body detects a virus or bacteria, the immune cells usually release pyrogen.

This is a signal to your brain to increase your body temperature. The fever (increase in your body temperature) helps fight pathogens as many bacteria and viruses struggle to thrive in the hot environment (your body).

On the other hand, allergies happen whenever your body overreacts to perceived invaders such as pet dander, dust, or pollen. The reaction causes your body to release inflammatory compounds, such as histamines, that cause different symptoms.

Note that fever-causing pathogens aren’t part of this natural immune system response. Here are the common infections that occur alongside allergy symptoms.

Sinusitis

Also known as sinus infection, sinusitis causes swelling and infection of the sinuses. It is a fever-causing infection that can be triggered by allergies and colds.

Sinuses are spaces in your head, particularly around your eyes, cheeks, and nose. They secrete mucus that usually drains through your nose to keep it clean and prevent infections. Sinuses are often filled with air. However, when blocked, they swell, and mucus may not drain out. This buildup can lead to bacterial infection (sinusitis).

Flu

This is a contagious respiratory infection caused by influenza viruses. It affects the throat, nose, and sometimes lungs. Flu symptoms may include chest congestion, sore throat, runny nose, headache, fever that lasts two days, body aches, headache, and more.

Common Cold

The common cold is another contagious upper respiratory illness that affects your trachea, nose, throat, and sinuses. Common cold symptoms may include sore throat, sneezing, headache, stuffy or runny nose, cough, and body aches.

Allergy Symptoms

Most allergic symptoms are associated with your body’s reaction to allergens such as dust mites, feathers or furs from animals, pollen, mold, and more. Hay fever is also an allergic reaction. Common symptoms of allergies include headaches, runny nose, sneezing, coughing, sore throat, wheezing, and more. Remember, fever isn’t an allergic reaction.

Diagnosis and Treatment

If you have a fever, consult your doctor to determine the cause. The physician will perform some tests, a physical exam, and review your medical history. For allergies, you will need to consult an allergist. They’ll likely perform tests to determine the environmental allergies you may have, such as dust mites, pollen, or pet dander.

A physician may prescribe antihistamines, immunotherapy, or nasal corticosteroids, depending on the allergic reaction involved. If you have a fever, your physician may recommend rest, a lukewarm bath, staying hydrated, a warm compress, or medication. Do Allergies Cause Fever?