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Allergies occur when your body mistakes a normally harmless substance (called an allergen) for a threat, triggering an immune response that is intended to protect you but in fact simply causes your allergy symptoms.1 This reaction can be sparked by a wide range of allergens, from pollen, pet dander, dust and mold to foods, medicines, latex and insect bites.

Allergic reactions are incredibly common, with more than 50 million Americans experiencing allergy symptoms each year.1 That’s why it’s important to know how to spot the signs of an allergic reaction in yourself or someone else, and what to do next – either treat the symptoms yourself, or seek medical help.

It is important to note, however, that FLONASE products are only to be used for relief from symptoms of allergic rhinitis – an allergic reaction to airborne allergens, such as pollen or dust; or year-round allergens, such as pet dander.

For treatment of other allergic reactions mentioned below, seek medical attention.



The symptoms of an allergic reaction can range from mild to severe, and vary from person to person. They also differ according to the allergen involved. Most symptoms affect the nose, eyes, skin, digestive system or mouth and airways. The most common symptoms include:2

  • Itchy, watery eyes
  • Sneezing
  • Runny nose
  • Nasal congestion
  • Itchy, red or peeling skin
  • Rashes or hives
  • Swelling, especially around the face
  • Wheezing or shortness of breath
  • Increased pulse
  • Dizziness



For symptoms of hay fever and other relatively mild allergies, over-the-counter (OTC) treatments and allergen avoidance can usually bring relief.

Of course, one of the best ways to stop an allergic reaction from happening is simply to avoid any known triggers. Read our tips for reducing your exposure to indoor and outdoor allergens.

Allergy pills and nasal sprays

Antihistamines are designed to help block histamine, one of the substances your immune system produces in response to allergens. Histamine causes many allergy symptoms, such as sneezing, runny nose and itchy, watery eyes, and antihistamine medications can help stop the reaction and bring relief.1

Depending on the location of your symptoms, you may opt for pills, liquids, nasal sprays or eye drops. Both over-the-counter and prescription antihistamines are available. Note that some antihistamines can cause drowsiness.1

If your nose is stuffed up, an OTC or prescription nasal decongestant pill or spray may be more useful. These medicines reduce inflammation within the nasal passages to ease congestion.

For relief of a wider spectrum of symptoms, an allergy nasal spray can be useful. FLONASE products help block not just histamine*, but five other inflammatory substances produced by your immune system, which means these products can relieve nasal congestion, plus itchy, watery eyes, runny nose and sneezing. Always read the label prior to use.

*Mechanism vs most over-the-counter (OTC) allergy pills. FLONASE nasal sprays act on multiple inflammatory substances (histamine, prostaglandins, cytokine, tryptases, chemokine, and leukotrienes). The exact number and precise mechanism are unknown.
FLONASE SENSIMIST is indicated for itchy, watery eyes in adults and children 12 years of age and older. See product pages for full information.

When to see your doctor

If your allergy symptoms are more serious or do not respond to OTC medications, consult your doctor or a specialist.



A particularly severe allergic reaction can cause the body to go into a state of shock. This condition is called anaphylaxis, or anaphylactic shock. If you think someone is experiencing anaphylaxis, seek emergency medical help right away:1,2,3



If you suspect that you or someone else may be going into anaphylactic shock, call 911 immediately. Note that symptoms of anaphylaxis may start off mild, but can rapidly escalate.1

Check if the person has an epinephrine auto-injector (commonly called an EpiPen) with them, or if one is available.



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  1. Medical News Today. How do you treat an allergic reaction? Accessed November 20, 2019
  2. Healthline. Allergic Reaction First Aid: What to Do. Accessed November 20, 2019.
  3. WebMD. Allergies and Anaphylaxis. Accessed November 20, 2019.
  4. WebMD. Children’s Allergic Reactions: What’s Severe? Accessed November 20, 2019.
  5. MedlinePlus. Nasal corticosteroid sprays. Accessed November 20, 2019.
  6. Decongestants: OTC Relief for Congestion.