Seasonal allergies, also known as allergic rhinitis, do not typically cause a fever. While they can cause a variety of uncomfortable symptoms, an elevated body temperature usually indicates a different underlying health issue, often an infection.
Understanding Seasonal Allergies
Seasonal allergies develop when the body’s immune system overreacts to harmless airborne particles like pollen from trees, grasses, or weeds. This reaction involves the production of immunoglobulin E (IgE) antibodies, which then trigger the release of chemicals like histamine, causing inflammation in the nasal passages and other areas.
Common symptoms include sneezing, a runny or blocked nose, itchy eyes, nose, throat, or roof of the mouth, and a cough. The term “hay fever” is misleading, as seasonal allergies do not cause a fever.
Understanding Fever
A fever is defined as an elevation of the body’s core temperature above its normal range, generally considered to be 100.4°F (38°C) or higher when measured orally. This indicates the body’s immune system is actively fighting an infection or illness. The hypothalamus, located in the brain, acts as the body’s thermostat and resets to a higher temperature during an infection.
Fevers are most commonly caused by infections, such as viruses like the common cold or influenza, or by bacterial infections. Other causes can include inflammatory conditions, certain medications, or vaccinations. A fever is a systemic response affecting the entire body, unlike the localized inflammatory reaction seen in allergic responses. The severity of a fever does not always correlate with the seriousness of the underlying condition.
When Allergy-Like Symptoms Occur With Fever
When symptoms resembling allergies, such as a runny nose, sneezing, and congestion, occur alongside a fever, it typically points to a viral infection rather than an allergic reaction. Viral illnesses like the common cold or the flu share many upper respiratory symptoms with allergies, which can lead to confusion. However, viral infections frequently include additional symptoms like body aches, fatigue, sore throat, and a cough, which are not typical of allergies alone.
Allergies often present with very itchy eyes, which is less common with viral infections. In some cases, prolonged allergic inflammation or congestion can predispose an individual to develop a secondary infection, such as a sinus infection. A sinus infection, characterized by inflammation of the sinuses, can cause symptoms similar to allergies and may indeed lead to a fever.
When to Seek Medical Guidance
If you experience a fever alongside allergy-like symptoms, seek medical guidance to determine the underlying cause. A healthcare professional can help differentiate between allergies, a viral infection, or a secondary bacterial infection like sinusitis.
Consider consulting a doctor if your fever is persistent, reaches 103°F (39.4°C) or higher, or if your symptoms worsen. Additionally, seek medical attention for severe symptoms such as a stiff neck, severe headache, confusion, difficulty breathing, or a rash.