Symbicort (budesonide/formoterol) is a prescription drug that’s used to treat certain breathing conditions. Symbicort can cause side effects that range from mild to serious. Examples include back pain, heart-related side effects, headache, and nasal congestion.

Symbicort is used to treat chronic obstructive pulmonary disease (COPD) in adults and asthma in adults and certain children. Symbicort is not meant to be used as a rescue inhaler for sudden breathing problems.

Symbicort contains two active ingredients: budesonide and formoterol. (The active ingredients are what make the drug work.) Symbicort comes in a metered-dose inhaler which releases the drug as a spray you breathe in through your mouth.

Keep reading to learn about the common, mild, and serious side effects that Symbicort can cause. For a general overview of the drug, including details about its uses, see this article.

Some people may experience mild to serious side effects during their Symbicort treatment. Common side effects reported in studies of people using Symbicort include:

* To learn more about this side effect, see the “Side effects explained” section below.

Side effects of Symbicort are generally mild. Mild side effects that have been reported with this drug include:

In most cases, these side effects should be temporary. And some may be easily managed. But if you have symptoms that are ongoing or bother you, talk with your doctor or pharmacist. And do not stop using Symbicort unless your doctor recommends it.

Symbicort may cause mild side effects other than those listed above. See the drug’s prescribing information for details.

* To learn more about this side effect, see the “Side effects explained” section below.

It’s possible to have serious side effects from Symbicort, but these are usually rare. Serious side effects that have been reported with this drug include:

If you develop serious side effects while using Symbicort, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

* To learn more about this side effect, see the “Side effects explained” section below.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Symbicort, visit MedWatch.

Get answers to some frequently asked questions about Symbicort’s side effects.

Can Symbicort cause anxiety?

It’s not likely. Anxiety was not a side effect reported in Symbicort studies. But it is one of the side effects of formoterol (an active ingredient* in Symbicort).

Some people can have serious side effects with Symbicort, such as bronchospasm (tightening of the airways) and worsening asthma symptoms. And these side effects may cause you to feel anxious. Anxiety is also one of the symptoms of asthma, a condition Symbicort is used to treat.

If you experience anxiety with Symbicort use, call your doctor. They can discuss possible causes with you and recommend ways to help manage it.

* An active ingredient is what makes a drug work.

Is weight gain a side effect of Symbicort?

No, people using Symbicort in studies did not report weight gain. But Symbicort contains two active ingredients: budesonide (a corticosteroid) and formoterol (a long-acting beta-agonist). And corticosteroids can cause weight gain.

Keep in mind, there may be other causes for weight gain, such as other medications you take.

If you’re wondering about weight gain with Symbicort, ask your doctor about it. They can provide more information, including the likelihood of this happening to you and ways to help manage it.

Will Symbicort’s side effects go away?

Yes, Symbicort’s side effects go away in most cases. In the drug’s studies, side effects were usually mild and went away within a few days to weeks of treatment.

However, long-term Symbicort use can increase your risk of certain side effects, including:

Your doctor will monitor you for long-term side effects throughout your Symbicort treatment. Do not stop using Symbicort without talking with them first. Stopping this medication may worsen your condition.

Talk with your doctor about the benefits and risks of long-term Symbicort use.

Learn more about some of the side effects Symbicort may cause.

Back pain

Symbicort can cause back pain. This was a common but mild side effect of the drug reported in studies. This may be temporary and ease with continued Symbicort treatment.

What might help

If you have back pain with Symbicort treatment, tell your doctor. For mild cases, they may suggest ways to relieve your back pain, such as:

But if you have serious back pain, call your doctor. They can diagnose the cause and treat it.

Heart-related side effects

Symbicort can cause certain heart-related side effects. These are rare but serious side effects of the drug reported in studies. Examples include:

What might help

If you experience serious heart-related side effects with Symbicort treatment, call your doctor. They can determine whether you should continue using the drug. If they recommend stopping Symbicort, they’ll be able to offer other, safer treatment options for managing your condition.

Headache

It’s possible for Symbicort to cause headaches. This was a common but mild side effect reported in the drug’s studies. Sometimes, side effects of Symbicort, such as sinusitis (sinus infection), can cause headaches. They may also be caused by other conditions, including high blood pressure, which is a serious side effect of Symbicort.

What might help

If you have headaches with Symbicort use, tell your doctor. They can try to determine the cause and suggest a treatment based on the cause and severity of your headaches.

For a mild headache they may suggest:

If your headaches are severe, your doctor may switch you to a different medication.

Oral thrush

Symbicort can sometimes cause an oral fungal infection called thrush. It’s caused by a yeast infection known as candidiasis. This was a common but mild side effect of the drug reported in studies of people using Symbicort for asthma or COPD.

Thrush can be caused by budesonide (an active ingredient* in Symbicort), which is a corticosteroid. Symptoms of thrush include:

  • pain or trouble swallowing
  • bad taste in your mouth
  • irritation, redness, or pain under dentures
  • burning or soreness inside your mouth
  • white or yellow spots on your tongue, gums, lips, inside of your cheeks, or tonsils

* An active ingredient is what makes a drug work.

What might help

The manufacturer of Symbicort recommends rinsing your mouth with water without swallowing right after your dose of Symbicort. This can help lower your chances of getting thrush.

If you notice symptoms of thrush, call your doctor right away. It’s important to diagnose and treat this condition immediately to stop the infection from spreading in your body. Sometimes, your doctor may suggest stopping Symbicort temporarily until you’ve been treated for thrush.

Allergic reaction

Like most drugs, Symbicort can cause an allergic reaction in some people. Symptoms can be mild to serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin (usually in your eyelids, lips, hands, or feet)
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms. Examples include:

If your doctor confirms you’ve had a mild allergic reaction to Symbicort, they’ll decide if you should continue using it.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Symbicort, they may have you switch to a different treatment.

Keeping track of side effects

During your Symbicort treatment, consider taking notes on any side effects you’re having. You can then share this information with your doctor. This is especially helpful when you start using a new drug or combination of treatments.

Your side effect notes can include things such as:

  • what dose of the drug you were using when you had the side effect
  • how soon you had the side effect after starting that dose
  • what your symptoms were
  • how your symptoms affected your daily activities
  • what other medications you were taking
  • any other information you feel is important

Taking notes and sharing them with your doctor will help them learn more about how Symbicort affects you. They can then use this information to adjust your treatment plan if needed.

Symbicort may not be right for you if you have certain medical conditions. (This is known as a drug-condition interaction.) Other factors may also affect whether Symbicort is a good treatment option for you. Talk with your doctor about your health history before starting this medication. Factors to consider include those described below.

Increased risk of infection. Corticosteroids can weaken your immune system and make you more vulnerable to infection. One of the active ingredients* in Symbicort (budesonide) is a corticosteroid. If you already have a weakened immune system, your risk of serious infection is higher with Symbicort use.

Be sure you’re up to date on all your vaccines, including those for chicken pox and measles, before starting treatment with Symbicort. Do not start this medication if you have an infection. Your doctor will likely treat your infection before prescribing Symbicort for you.

If you have a weakened immune system, your doctor may recommend a different, safer treatment for your condition.

* An active ingredient is what makes a drug work.

Eye problems. Tell your doctor if you have any eye problems, such as cataracts or glaucoma. Corticosteroids can worsen eye problems. Budesonide (an active ingredient in Symbicort) is a corticosteroid. If you already have eye conditions, Symbicort may worsen them.

Your doctor will determine whether Symbicort is right for you if you have serious eye problems. If they prescribe this medication for you, they’ll monitor you for changes to your eyes.

Thyrotoxicosis. If you have a thyroid disorder, Symbicort may not be right for you. Using Symbicort when you have thyrotoxicosis (too much thyroid hormone) could increase your risk of serious side effects such as seizure, congestive heart failure, muscle weakness, and confusion.

Tell your doctor if you have any thyroid conditions such as hyperthyroidism. They’ll decide if it’s safe for you to use Symbicort.

Use of oral corticosteroids. If you’re taking an oral corticosteroid such as prednisone, tell your doctor. They’ll have you gradually stop the corticosteroid before starting Symbicort. Stopping oral corticosteroids too quickly can cause serious side effects such as adrenal insufficiency (adrenal glands not making enough hormones). In rare cases, this can cause death. Your doctor will decide when it’s safe for you to start Symbicort.

Osteoporosis. Corticosteroids may weaken bone density. One of the active ingredients in Symbicort (budesonide) is a corticosteroid. Using Symbicort long term may cause osteoporosis. Tell your doctor if you have osteopenia or osteoporosis. Symbicort could worsen these conditions and increase your risk of bone fractures.

Your doctor will decide if Symbicort is safe for you. Your risk of bone-related problems is higher if you’re older, smoke, or have gone through menopause. If your doctor prescribes Symbicort, they’ll monitor you closely for changes in your bone density.

Allergic reaction. If you’ve had an allergic reaction to Symbicort or any of its ingredients, your doctor will likely not prescribe it for you. Ask them about other medications that might be better options.

Heart and central nervous system conditions. If you have heart disease, using Symbicort may increase your risk of certain side effects. See the “Side effects explained” section above for more information on heart-related side effects of Symbicort.

Symbicort can also cause certain central nervous system (CNS) conditions, such as seizure, headache, dizziness, and tremors. If you have a seizure disorder or other CNS condition, Symbicort may increase your risk of CNS side effects.

Tell your doctor about your health history, including any heart- or CNS-related conditions. They’ll decide if Symbicort is safe for you.

Acute severe asthma. If you have acute severe asthma, Symbicort may not be the best treatment for you. Tell your doctor if you have this condition. They can recommend a safer option for treating your asthma or COPD.

Diabetes and hypokalemia. Tell your doctor if you have diabetes or hypokalemia (low blood potassium levels). Symbicort can increase blood sugar levels, especially in people with diabetes.

Symbicort can also cause a decrease in blood potassium levels. Changes in potassium levels can cause problems with your heart. If you already have a heart condition, this could worsen it. In studies of the drug, these effects were temporary.

If your doctor determines that Symbicort is a good treatment option for you, they’ll monitor your blood sugar and potassium levels for changes.

Alcohol and Symbicort

There are no known interactions between Symbicort and alcohol. But drinking alcohol can increase your risk of side effects from Symbicort if:

  • you’re taking other drugs for your asthma or COPD
  • you have certain health conditions, such as high blood pressure

If you plan to drink alcohol, ask your doctor what amount, if any, is safe to consume during treatment with Symbicort.

Pregnancy and breastfeeding with Symbicort

There are no studies of Symbicort use during pregnancy, so it’s unknown whether the drug is safe to use during this time. But untreated asthma can cause problems during pregnancy, such as:

If you’re pregnant or planning to become pregnant and you have asthma or COPD, talk with your doctor about the safety of Symbicort use. They can provide more information about your options.

It’s also not known whether Symbicort is safe to use while breastfeeding. If you’re planning to breastfeed, ask your doctor about the potential benefits and risks of Symbicort for you and your child.

Most of the common side effects of Symbicort are mild, but in rare cases, the drug can cause serious side effects that require medical attention. Understanding the side effects of Symbicort may help you manage them.

If you have questions about side effects this drug can cause, talk with your doctor. A few examples of questions to help get you started include:

  • How do the side effects of Symbicort compare to those of Trelegy Ellipta?
  • Do the side effects of Symbicort vary based on dosage?
  • Do I have an increased risk of headaches from Symbicort if I already have migraine episodes?

To learn more about Symbicort, see these articles:

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Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.