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How Does Flonase Work?

If you’re a Flonase customer, you already know to turn to Flonase for 24-hour relief when your allergies start to flare up. However, what does Flonase do once it enters your nose, and how is it different from other competing products? With so many different nasal sprays on the market, how do you know if you’ve chosen the right one for your allergies? Learn how Flonase works vs. other allergy-relief sprays so you can feel confident that you’re treating your allergy symptoms effectively. 

What Causes Allergies?

Your body’s immune system protects you by battling with foreign threats that enter your system. However, your body sometimes overreacts to a perceived threat that is actually harmless.1,2 Allergies, also known as hay fever, occur when your body’s immune system is triggered by something in your environment and has a strong reaction to it. Allergens, including mold or airborne spores and pollen, enter through your nose or mouth, causing your body to release the inflammatory substances that cause allergy symptoms, including:1

  • Runny nose
  • Watery, itchy eyes
  • Itchy nose
  • Sneezing
  • Nasal congestion

What Are Histamines?

When a foreign substance enters your body, your immune system releases chemicals to try and fight off the intruder. Histamine is one of the various substances your body produces when it overreacts to an allergen, such as pollen, dust, spores or pet dander. Histamine can cause you to feel allergy symptoms, including sneezing and an itchy nose.2

However, while histamine is partially responsible for your symptoms, your body creates other inflammatory substances that cause allergies. Instead of targeting histamine alone, Flonase targets six allergy substances, including histamine.

What Is the Active Ingredient in Flonase?

The active ingredient in Flonase Allergy Relief Spray is the nonprescription version of fluticasone, a corticosteroid that works by blocking the release of the substances that cause allergies.3 Many allergy pills on the shelves are single-ingredient antihistamines, meaning they only block the production of histamine. Unlike antihistamines, Flonase blocks six allergy-causing substances, including histamine*, to relieve nose and eye allergy symptoms, including nasal congestion, runny nose, sneezing, itchy, watery eyes and an itchy nose. Flonase nasal sprays are also non-addictive and don’t cause drowsiness.

Flonase Sensimist is like regular Flonase, except it comes in a gentle mist that you can barely feel. Using patented MistPro technology, Flonase Sensimist creates a fine, lightweight mist that’s scent free and causes virtually no drip for adults and children aged twelve and older.

What’s the Difference Between Flonase and Astepro?

Astepro Nasal Spray uses the active ingredient Azelastine—an antihistamine that treats allergy symptoms including a runny nose, sneezing and an itchy nose.4 Azelastine isn’t in the same class of drugs as fluticasone, and it’s not considered a corticosteroid. Azelastine is an antihistamine, meaning it blocks the production of histamine in your body.2 However, unlike fluticasone, azelastine only blocks the production of histamine.*

What About Children’s Flonase?

Children’s Flonase is the #1 pediatrician-prescribed allergy medicine and relieves allergy symptoms in children ages 4 and up. Unlike antihistamines, which only block histamine, Children’s Flonase blocks six allergic substances at their source.* It helps relieve a runny nose, sneezing, itchy nose, itchy, watery eyes and nasal congestion. Children’s Flonase Sensimist provides the same child-friendly allergy relief in a gentle mist your kids will barely feel for children ages two and up.

Now that you know how Flonase compares to other allergy medications, you’re ready to choose the best product to treat your allergies. To become an allergy expert, read more about allergies 101 on our All About Allergies hub.

*Mechanism vs. most OTC allergy pills. Flonase acts on multiple inflammatory substances (histamine, prostaglandins, cytokines, tryptases, chemokines and leukotrienes). The exact number and precise mechanism are unknown.

Source Citations:

  1. Allergies and the Immune System | Johns Hopkins Medicine. https://www.hopkinsmedicine.org/health/conditions-and-diseases/allergies-and-the-immune-system. Accessed 9/22/22.
  2. Antihistamines: Definition, Types & Side Effects. https://my.clevelandclinic.org/health/drugs/21223-antihistamines. Accessed 9/22/22.
  3. Fluticasone Nasal Spray: MedlinePlus Drug Information. https://medlineplus.gov/druginfo/meds/a695002.html. Accessed 9/22/22.
  4. Azelastine Nasal Spray: MedlinePlus Drug Information. https://medlineplus.gov/druginfo/meds/a697014.html. Accessed 9/22/22.
  5. Astepro® Allergy Nasal Antihistamine Spray. https://www.asteproallergy.com/products/astepro-allergy-nasal-spray. Accessed 9/22/22.