Nasacort vs Flonase: What’s the Difference?

If you’re one of the more than 50 million Americans who struggles with allergies throughout the year, you understand the frustration of trying to manage your allergy symptoms while still engaging in all of the daily activities that you love.

Suddenly, a simple hike becomes a much more complicated ordeal as you struggle to figure out the latest pollen levels and try different medications in order to manage your allergy symptoms well enough to enjoy your outing.

Allergies are the sixth most common chronic illness in the United States and the number one most common health issue for children.

While antihistamine pills and medications like Benadryl, Claritin, and Allegra have often been many people’s first line of defense against nasal symptoms and allergy symptoms, allergy sprays and nasal sprays like Nasacort and Flonase can be just as, if not more, effective at treating allergy symptoms.

When trying to choose between Nasacort vs Flonase, it’s important to understand the similarities and differences between these two over the counter (OTC) allergy relief medications. 

Drug Class

Nasacort allergy 24hr and Flonase allergy relief both belong to a class of drugs called corticosteroids; specifically,  they are synthetic glucocorticoid nasal steroids.

Unlike antihistamine medications, such as Benadryl, Allegra, and Claritin, which block one cause of allergic substances in the body (histamines), Nasacort and Flonase nasal corticosteroid sprays block six key allergic substances, including histamines, to provide relief.

When exposed to allergens, our bodies produce a variety of allergic substances that cause nasal allergy symptoms, including nasal congestion, itchy, watery eyes, sneezing, and more.

Studies have shown that nasal corticosteroids like Nasacort and Flonase provide more complete and effective relief for allergy symptoms than oral antihistamines because they block more of the allergic substances released by the body after exposure to an allergen. 

Conditions Treated

When most people say they have allergies, they are actually referring to allergic rhinitis, which is a group of reactions that occur when the body is exposed to an allergen.

Allergens are common substances found in both indoor and outdoor environments that normally do not cause a reaction but can produce strong allergy symptoms in others. When a person has allergies to a specific substance, their immune system responds to the presence of that substance by attacking it.

During the attack, a number of different inflammatory mediators, including histamines, are released during an allergy attack.

These mediators bind to receptors on a variety of cells in the body, particularly in the nasal passages, and cause the symptoms of allergic rhinitis, which include sinus pressure, nasal congestion, runny nose, sneezing, itchy/watery eyes, and itchy nose or throat.

Allergic rhinitis can be triggered by many different substances, including those found indoors and outdoors. Indoor allergens commonly include substances like mold, pet dander, pet hair, dust mites, smoke, and perfume, while outdoor allergens include things like pollen from grasses, flowers, trees, or weeds.

When a person is allergic to outdoor allergens, they most commonly experience allergy symptoms on a seasonal allergies basis, while those with indoor allergens are likely to experience symptoms year round.

A person can be allergic to both indoor and outdoor substances and experience some symptoms of allergic rhinitis seasonally and others perennially. 

How it Works

Glucocorticoid steroids like Nasacort and Flonase work by reducing the inflammation and swelling that comes with allergic responses to allergens.

Corticosteroids are considered more effective than antihistamines for treating allergy symptoms because they block allergic responses from six different types of cells in the nasal passages, while oral antihistamines only block responses caused by histamines.

When the nasal passages become inflamed during an allergy attack, symptoms like sneezing, runny nose, and other upper respiratory symptoms occur. Corticosteroids reduce the inflammation, thereby reducing the symptoms. 


Nasacort, also sold under the generic name triamcinolone acetonide, is available in the form of a nasal spray that provides 55 mcg of the active ingredient.

Flonase, which is also sold under the generic name fluticasone propionate, is sold in the form of a nasal spray that delivers 50 mcg of the active ingredient. Flonase is also available in a formula that is specially designed for children, as is Nasacort.

Flonase recently developed a new line of products called Flonase Sensimist that produce the nasal spray as a gentle mist that does not include any alcohol or have a noticeable scent. Some nasal sprays also cause post nasal drip, which has been eliminated by the Sensimist line.  


One of the most substantial differences between Nasacort and Flonase is the use instructions for the medications.

Nasacort is intended for short term use, typically of one week or less, while Flonase can be used for up to six months in adults and two months in children.

Nasacort is approved for use in adults and children ages 2 and older, while Flonase is approved for use and adults and children ages 4 and older. 


When choosing between Nasacort and Flonase, one thing you don’t have to worry about is major differences in the effectiveness of the medications. In study after study, Flonase and Nasacort have been proven equally effective in the treatment of allergic rhinitis symptoms.

Therefore, the choice in which medication to take often comes down to personal preference and the length of time that the medication is needed.

However, there is one key difference between the medications when it comes to effectiveness; Flonase is FDA-approved to treat allergy symptoms associated with the eyes, such as itchy, watery eyes, while Nasacort is not.

Therefore, if eye symptoms are a significant part of your body’s allergic response, you may be better suited to taking Flonase, as it is more likely to alleviate your symptoms completely. 


One of the best things about Nasacort and Flonase is that both medications are sold over the counter, meaning that patients can purchase them at any pharmacy, drug store, or big box store.

Both medications are sold in a generic form as well as the brand name form, and the generic versions can be purchased extremely inexpensively at warehouse membership clubs like Costco and Sam’s Club.

In general, using pharmacy discount cards like USA Rx, you can expect to pay about 12 to 13 dollars for the generic forms of both Flonase and Nasacort, or about half of the price of the brand name version, for a total of 120 sprays. 


Both Flonase and Nasacort are sold over the counter, which means they are generally considered safe for use by most people.

However, corticosteroid nasal sprays like Flonase and Nasacort do carry some risks of use, particularly for people with certain medical conditions.

Although the medications are sold over the counter, it is important that you speak to your doctor before taking Flonase or Nasacort if you have any of the following conditions:

  • Nose sores, injury, or surgery
  • Eye infections
  • Tuberculosis
  • Eye infections caused by herpes
  • Liver problems
  • Eye problems such as cataracts or glaucoma
  • Weakened immune system
  • Any untreated viral, bacterial, or fungal infection
  • Recent exposure to chickenpox or measles

Side Effects

As over the counter medications, both Flonase and Nasacort are considered safe medications with a relatively low incidence of side effects.

However, some side effects may occur. Side effects of Nasacort and Flonase are generally similar, with a few exceptions. Common side effects of Nasacort that usually do not include medical attention include:

  • Headache
  • Bloody nose
  • Burning, irritation, or inflammation in the nose
  • Sneezing
  • Sore throat
  • Cough

Common side effects of Flonase that usually do not include medical attention include:

  • Headache
  • Bloody nose
  • Burning, irritation, or inflammation in the nose
  • Asthma symptoms
  • Sore throat
  • Cough

Although rare, it is also possible for both Flonase and Nasacort to cause serious side effects that may require medical attention, including allergic reactions.

Serious side effects of Nasacort that may require medical attention include:

  • Nose bleeds and sores in the nose
  • Decreased wound healing
  • Cataracts
  • Worsening of infections
  • Wheezing or trouble breathing
  • Puncture of the nasal septum
  • Glaucoma
  • Severe allergic reaction
  • Slowed growth rate in children and adolescents
  • Feeling of pins and needles in the hands or feet

Serious side effects of Flonase that may require medical attention include:

  • Nose bleeds and sores in the nose
  • Decreased wound healing
  • Cataracts
  • Worsening of infections
  • Puncture of the nasal septum
  • Glaucoma
  • Severe allergic reaction
  • Slowed growth rate in children and adolescents

Drug Interactions

Both Flonase and Nasacort have a relatively short list of drug interactions, but patients should be sure to check the list of drug interactions for any medications they may be taking to ensure that the use of Nasacort or Flonase will not impact the effectiveness of their other medications.

If you are unsure about drug interactions between your current medications and Flonase or Nasacort, speak to your doctor or pharmacist.  Nasacort may interact with the following medications:

  • Chemotherapy drugs
  • Sirolimus
  • Basiliximab
  • Muromonab-CD3
  • Azathioprine
  • Etanercept
  • Cyclosporine
  • Tacrolimus
  • Efalizumab
  • Mycophenolate mofetil
  • Leflunomide

Flonase may interact with certain HIV medications including:

  • Ritonavir
  • Indinavir
  • Saquinavir
  • Atazanavir
  • Nelfinavir
  • Lopinavir


Ultimately, Nasacort and Flonase are very similar and equally effective medications. The choice between the two drugs often comes down to personal preference, cost, and availability.

However, if you suffer from eye symptoms as part of your allergy symptoms, Flonase is likely to be the better choice, as it is FDA-approved for the treatment of allergy eye symptoms.

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