Budesonide/formoterol (Symbicort)

What budesonide/formoterol is and how it works

Symbicort is a prescription-only combination inhaler containing an inhaled corticosteroid (budesonide) and a long-acting beta2-agonist (formoterol), used regularly to control asthma and chronic obstructive pulmonary disease (COPD). It is not a rescue inhaler for a sudden asthma or COPD attack in most markets. (1) (4)

Use Symbicort exactly as your prescriber directs, usually twice daily, even when you feel well -- it works best as regular, ongoing treatment rather than an as-needed rescue medicine. In the United States, Symbicort is not used to relieve sudden breathing difficulty; keep a separate fast-acting reliever inhaler on hand for that, as directed by your prescriber. (Some other countries license certain Symbicort products for combined maintenance-and-reliever use -- follow your own country's product information and your prescriber's instructions.)

Mechanism of action: how budesonide/formoterol works

Budesonide is an anti-inflammatory corticosteroid with high glucocorticoid receptor affinity; formoterol is a selective, long-acting beta2-adrenergic agonist with a rapid onset of bronchodilation. Combining the two provides both anti-inflammatory control and sustained bronchodilation. (1)

What budesonide/formoterol is used for

Before taking budesonide/formoterol

Do not take / not appropriate for

• Symbicort is not for the primary treatment of a severe, ongoing asthma attack (status asthmaticus) or other acute asthma/COPD episodes requiring intensive medical measures -- these need different, faster emergency treatment. (all countries) (1)
• Do not use Symbicort if you have had a serious allergic reaction to budesonide, formoterol, or any of its ingredients. (all countries) (1)
• Do not use Symbicort together with another medicine containing a long-acting beta2-agonist (LABA), because of an increased risk of overdose-related effects. (all countries) (1)

Tell your clinician about

• Any heart problems, high blood pressure, an irregular heartbeat, or a seizure disorder.
• Any current or past infections, including tuberculosis, or any eye infection with the herpes virus.
• Whether you have ever had chickenpox or measles, or have not been exposed to them, since inhaled corticosteroids can allow a more serious course of either illness in susceptible people.
• Any liver problems, diabetes, low potassium levels, osteoporosis or reduced bone density, glaucoma, or cataracts.
• If you are currently taking, or have recently taken, oral (tablet) corticosteroids.
• All other medicines, especially other asthma or COPD inhalers, beta-blockers, diuretics ('water tablets'), antidepressants (particularly MAOIs or tricyclics), or strong CYP3A4-inhibiting medicines such as ritonavir, ketoconazole, clarithromycin, itraconazole, or nelfinavir.
• Pregnancy, plans for pregnancy, or breastfeeding.

How to take budesonide/formoterol

• Use Symbicort regularly, exactly as your prescriber directs, even when you have no symptoms -- it is a maintenance treatment, not typically a rescue inhaler in the United States.
• Rinse your mouth with water and spit it out (without swallowing) after each use, to help reduce the risk of oral thrush (candidiasis).
• Do not stop or change your dose on your own; any change to your Symbicort dose, or to any oral corticosteroid you are also tapering off, should be directed by your prescriber.
• If you have been using an oral (tablet) corticosteroid, your prescriber will supervise how it is tapered when starting Symbicort, since adrenal function can be affected during this transition.

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6) (7)

Missed dose

Take the next dose at its regular scheduled time; contact your prescriber or pharmacist for guidance if you are unsure, rather than taking an extra dose to make up for the one you missed.

Overdose

Seek urgent medical attention or contact a poison control centre if too much Symbicort has been used, or if you notice symptoms such as a fast or irregular heartbeat, chest pain, tremor, nausea, or seizures. (1)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Serious warnings

Interactions

• Strong CYP3A4-inhibiting medicines (such as ritonavir, ketoconazole, clarithromycin, itraconazole, or nelfinavir) can increase systemic corticosteroid effects -- tell your prescriber if you take any of these. (1)
• MAOIs and tricyclic antidepressants may increase formoterol's effect on the heart and blood vessels -- these combinations need extra caution from your prescriber. (1)
• Beta-blocker medicines may block Symbicort's airway-opening effect and can trigger severe bronchospasm. (1)
• Diuretics ('water tablets') combined with a beta-agonist can worsen heart rhythm changes or low potassium levels. (1)
• Other medicines containing a long-acting beta2-agonist should not be combined with Symbicort because of an increased risk of overdose-related effects. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Monitoring

Before starting

• Baseline lung function assessment
• Review of cardiovascular risk factors and current medicines
• Bone density assessment where long-term inhaled corticosteroid use is anticipated

During treatment

• Periodic lung function monitoring to guide treatment.
• Growth monitoring in children and adolescents.
• Periodic bone mineral density assessment with long-term use.
• Watching for oral thrush, vision changes, and signs of adrenal suppression, especially when reducing oral corticosteroids.

Storage

Store at room temperature and follow the specific storage and priming/shaking instructions in the leaflet for your particular inhaler device; do not puncture, break, or burn the canister, and discard according to local guidance once the dose counter (where fitted) reaches zero.

Frequently asked questions

References

1. SYMBICORT (budesonide and formoterol fumarate dihydrate) Inhalation Aerosol -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), full prescribing information, AstraZeneca Pharmaceuticals LP · United States · accessed 2026-07-29 · source 1
2. FDA Updates SYMBICORT Label With LABA Safety Class Revisions and Removes Boxed Warning for Serious Asthma-Related Outcomes (December 2017)U.S. Food and Drug Administration / trade press summarising the FDA safety communication · United States · accessed 2026-07-29 · source 2
3. Symbicort forte Turbuhaler, Symbicort Turbuhaler, Symbicort mite Turbuhaler -- Public Assessment ReportSwedish Medical Products Agency (Lakemedelsverket/MPA) -- Reference Member State public assessment report for the EU mutual recognition procedure · European Union · accessed 2026-07-29 · source 3
4. Symbicort Turbohaler 200 micrograms/6 micrograms per actuation -- Summary of Product Characteristicselectronic medicines compendium (emc), United Kingdom -- AstraZeneca UK Limited · United Kingdom · accessed 2026-07-29 · source 4
5. SYMBICORT TURBUHALER (budesonide/formoterol fumarate dihydrate) Product MonographHealth Canada product monograph, AstraZeneca Canada Inc. · Canada · accessed 2026-07-29 · source 5
6. Symbicort Turbuhaler / Symbicort Rapihaler -- ARTG registrationTherapeutic Goods Administration (TGA), Australia · Australia · accessed 2026-07-29 · source 6
7. Symbicort Turbuhaler New Zealand Data SheetMedsafe (New Zealand regulator) · New Zealand · accessed 2026-07-29 · source 7

Brand names by country

Single-ingredient budesonide/formoterol names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries