When allergy season hits, many people experience symptoms that can feel similar to having a fever, leading to confusion about whether allergies can actually cause an elevated body temperature. Understanding the relationship between allergies and fever is crucial for proper diagnosis and treatment of your symptoms.
While allergies can cause various uncomfortable symptoms, it's important to know that allergies alone typically don't cause a true fever. However, the connection between allergies and body temperature is more complex than you might think, and certain complications from allergies can lead to conditions that do cause fever.
Understanding Allergy Symptoms vs. Fever
Allergies typically cause symptoms such as:
- Sneezing
- Runny or stuffy nose
- Itchy or watery eyes
- Fatigue
- Headache
- Postnasal drip
A true fever, defined as a body temperature of 100.4°F (38°C) or higher, is not a direct symptom of allergies. However, people might feel warm or flushed during allergy attacks, which can be mistaken for a fever.
Why Allergies Can Feel Like a Fever
During an allergic reaction, your body releases chemicals like histamine that can cause inflammation and increased blood flow. This can result in:
- Feeling warm or flushed
- Facial redness
- General discomfort
- Fatigue and weakness
These symptoms can mimic the sensation of having a fever, but when measured with a thermometer, your body temperature will typically be normal.
The Connection Between Allergies and Infections
While allergies themselves don't cause fever, they can create conditions that make you more susceptible to infections that do cause fever. When allergies cause inflammation in your sinuses and nasal passages, it can lead to:
- Blocked drainage passages
- Trapped mucus
- Bacterial growth
- Development of sinus infections (sinusitis)
When to Seek Medical Attention
You should consult a healthcare provider if you experience:
- A true fever (100.4°F or higher)
- Severe facial pain or pressure
- Thick, colored nasal discharge
- Symptoms lasting more than 10 days
- Worsening symptoms despite allergy medication
Frequently Asked Questions
Can you actually get a fever from allergies, or does something else cause it?
No, allergies alone don't cause fever. If you have a genuine fever along with allergy symptoms, it's likely due to a secondary infection, such as sinusitis or a viral infection.
Why do people sometimes mistake allergy symptoms for a fever, and how can I tell the difference?
People often mistake allergy symptoms for fever because allergies can cause warmth and flushing. The key difference is that allergies won't cause an actual elevation in body temperature. Use a thermometer to check if you have a true fever.
Can allergies lead to other infections like sinusitis that do cause a fever?
Yes, allergies can create conditions that make you more susceptible to sinus infections and other respiratory infections, which can cause fever. This happens when inflammation from allergies blocks normal sinus drainage.
When should I see a doctor if I have allergy symptoms along with a fever?
See a doctor if you have a fever above 100.4°F, severe sinus pain, thick colored mucus, or symptoms that last more than 10 days or don't improve with over-the-counter allergy medications.
How do you treat or prevent a sinus infection if you already have allergies?
To prevent sinus infections when you have allergies, manage your allergies effectively with appropriate medications, use nasal irrigation, stay hydrated, and keep your environment clean. If you develop a sinus infection, your doctor may prescribe antibiotics if it's bacterial.
