8 Flonase Side Effects You Should Know About

Allergy symptoms can be bothersome. You may be considering a nasal spray to help relieve them. Flonase Allergy Relief (fluticasone propionate) and Flonase Sensimist (fluticasone furoate) are two steroid nasal sprays available over the counter (OTC).

But what does Flonase do, and how does it work? Both versions of Flonase work by lowering your immune system’s response to allergens (substances that cause allergies). This helps lessen allergy symptoms, such as nasal congestion and sneezing.

But no medication comes without side effects. The good news is that Flonase is usually well tolerated. Most people have mild and temporary side effects, such as headache or a sore throat. But it’s still good to know about Flonase side effects and how to manage them should they happen to you.

EXPERT PICKS: WHAT TO READ NEXT

• Nasal sprays 101: Using your nasal spray correctly can help limit or prevent certain Flonase (fluticasone) side effects.

• How long does Flonase take to work? Flonase may begin to relieve allergy symptoms in 2 to 4 hours after your first dose. But it may take up to 2 weeks to get the full effects.

• Flonase for allergy symptoms: Real people share their experiences with Flonase, including what happens if they forget to take a dose.

Flonase (fluticasone propionate) side effects at a glance

Many people are able to use Flonase without any problems. And when issues do happen, they’re typically mild and are able to be managed at home. Serious adverse effects of Flonase are generally rare but still possible.

Common or mild Flonase side effects include:

• Headache

• Sore throat

• Nosebleeds

• Nasal burning or irritation

• Cough

• Hoarseness

• Voice changes

• Smell or taste changes

• Nausea

• Vomiting

Serious adverse effects of Flonase include:

• Oral or nasal thrush (a fungal infection of the mouth, throat, or nose)

• Nasal ulcers (open sores)

• Slowed growth in children

• Glaucoma

• Cataracts

• Asthma symptoms

• Allergic reactions

Keep in mind that this is not a complete list of all possible Flonase side effects. Speak to your healthcare team about any side effect that’s bothersome or doesn’t go away, even if it’s not listed here. They may suggest another allergy medication for you.

Below, we review eight potential Flonase side effects in more detail — plus ways to manage them.

1. Headache

Headaches are one of the most common Flonase side effects. This can be confusing, since sometimes Flonase can improve headaches caused by sinus pressure. Headaches were more common in clinical studies using higher doses of Flonase (2 sprays in each nostril per day).

If you have headaches while taking Flonase, here are some tips to try at home for relief:

• Drink plenty of water and other fluids.

• Exercise or add movement to your daily routine.

• Get adequate sleep at night.

• Take steps to lower your stress levels with activities, such as meditation or mindfulness.

You can also ask your healthcare team about taking an OTC pain reliever, such as ibuprofen (Advil, Motrin) or acetaminophen (Tylenol). These can help for occasional headaches. If your headaches don’t seem to get better or become severe, talk to a healthcare professional about next steps.

2. Sore throat

Sore throat is another common Flonase side effect. Gargling with water after using Flonase nasal spray may lessen the chance of sore throat.

If you have a sore throat when using Flonase, you can try these home remedies:

• Eat soft or soothing foods and avoid crunchy, spicy, or sour foods.

• Try a throat lozenge, such as Cepacol (benzocaine / menthol), or a spoonful of honey.

• Drink cold fluids or suck on ice chips.

• Use a humidifier.

As with headaches, you can ask a healthcare professional about using an OTC pain reliever for sore throat relief. If your sore throat gets worse or you develop other symptoms, such as a fever, contact your primary care provider (PCP). There may be another cause for your sore throat, such as an infection.

3. Nosebleeds and irritation

Nosebleeds are common in people who use steroid nasal sprays such as Flonase. This is because Flonase can thin the skin and blood vessels inside the nose. This thinning can also cause nasal irritation or burning.

Less often, Flonase can cause ulcers (open sores) in your nasal passages. This is a serious side effect. If you have a nosebleed, contact your PCP. Nosebleeds can be a symptom of nasal ulcers. They may ask you to stop using Flonase.

Certain people may be more prone to nosebleeds and ulcers. You shouldn’t use Flonase if you have a recent history of nasal ulcers, nasal surgery, or nasal trauma (such as a broken nose).

Using a humidifier may help with nasal burning or irritation. Saline nasal sprays or rinses may also help soothe these side effects. It can be helpful to use saline spray a few minutes before using Flonase. This can help moisturize the nose and may help reduce nosebleeds.

If you experience a nosebleed, here are a few steps to follow to help get it under control:

• Sit down and lean forward slightly to prevent blood from running down your throat.

• Pinch the bridge of your nose to apply pressure.

• Breathe through your mouth.

• Ice the bridge of your nose for up to 15 minutes.

4. Asthma symptoms

Asthma symptoms, such as coughing or wheezing, are a potential adverse effect of Flonase. Speak to your healthcare team before using Flonase if you have asthma. They can help you determine if it’s safe for you to use.

If you experience new or worse asthma symptoms while using Flonase, let your PCP know. Follow any asthma treatment regimens you already have, such as using a rescue inhaler.

5. Nausea or vomiting

Nausea and vomiting are possible side effects of many medications, including Flonase. But they are relatively uncommon for this nasal spray. It is possible that the medication dripping down your throat could cause an upset stomach. If you use Flonase properly, it can help limit or prevent this side effect.

If you find yourself nauseated after taking Flonase, here are some tips that may help:

• Stay hydrated.

• Eat smaller, more frequent meals.

• Avoid spicy and fatty foods.

• Take your Flonase doses at night before bed.

• Gargle with water after your doses.

• Try ginger or peppermint tea.

• Ask a healthcare professional about OTC nausea medications.

Nausea and vomiting from Flonase should get better or stop as your body adjusts to the medication. But if they don’t or they become severe, contact your PCP for next steps.

6. Thrush

In rare cases, people have developed nasal or oral thrush (a type of fungal infection) while using Flonase. As mentioned earlier, Flonase works by lowering your immune system’s response to allergens. But this can also raise your risk for infections. However, this risk is much lower with nasal steroids compared with oral or inhaled steroids. And you’re unlikely to experience body-wide infections, which is a risk with oral steroids.

Thrush from Flonase typically appears in the nose or throat. You may notice white or yellow patches in those areas. Other symptoms include a sore throat, changes in taste, and pain when swallowing.

The longer you use this nasal spray, the greater your risk of developing thrush. It’s best to use Flonase for the shortest amount of time needed to treat your symptoms. If you need to use it every day for more than 6 months (or 2 months for kids), it’s time to speak with your PCP.

If you develop thrush, you’ll likely need a prescription medication for treatment. Your PCP may also have you stop using Flonase until your infection is cleared.

7. Slowed growth in children

Nasal steroid sprays can stunt growth in children. A clinical study found that this side effect seems to appear around 2 months after starting treatment. It’s important to note that this study looked at another nasal steroid spray — not Flonase. But because the two nasal sprays are similar, Flonase’s manufacturer warns of the possibility of stunted growth.

Check with your child’s pediatrician before starting Flonase. They can help you choose the best treatment for your child’s symptoms. Depending on how long your child takes Flonase, their pediatrician may want to check their growth periodically. This can help them make sure your child’s growth is still on track for their age.

8. Eye problems

Flonase has a serious warning about the potential to develop glaucoma and cataracts. However, there’s debate about whether nasal steroids actually cause these problems. More recent studies suggest that medications such as Flonase don’t cause glaucoma or cataracts in people who otherwise have a low risk for these conditions.

Keep in mind that if you already have glaucoma or cataracts, Flonase could worsen them. And people with risk factors for developing these eye problems could be more likely to develop them if they use Flonase. Examples of risk factors include having diabetes or heart disease.

If you have these eye problems or a risk for developing them, ask your healthcare team before starting Flonase. Contact your PCP or eye doctor if you notice any vision changes after starting Flonase.

Are there problems with long-term use of Flonase?

Many people can safely use Flonase every day. But talk to your healthcare team if you feel like you need to use Flonase daily for longer than 6 months (or 2 months for children). Using Flonase long term may raise the risk of serious side effects, such as nasal ulcers. For children, there’s concern that long-term use could affect their growth.

If you’re using Flonase long term, your healthcare team may want to watch for signs of serious adverse effects.

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Written by:

Nicole E. Cieri-Hutcherson, PharmD, BCPS, NCMP

Nicole E. Cieri-Hutcherson, PharmD, BCPS, NCMP, has over a decade of experience as a pharmacist, professor, and researcher. She was a full-time clinical professor in the pharmacy practice department at D’Youville School of Pharmacy before subsequently joining the faculty of the pharmacy practice department at the University at Buffalo School of Pharmacy and Pharmaceutical Sciences.

Edited by:

Christina Aungst, PharmD

Christina Aungst, PharmD, is a pharmacy editor for GoodRx. She began writing for GoodRx Health in 2019, transitioning from freelance writer to editor in 2021.

Reviewed by:

Stacia Woodcock, PharmD

Stacia Woodcock, PharmD, is a pharmacy editor for GoodRx. She earned her Doctor of Pharmacy degree from the University of Kentucky and is licensed in New York and Massachusetts.

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