Symbicort contains two active ingredients: budesonide, an inhaled corticosteroid that reduces airway inflammation, and formoterol, a long-acting bronchodilator that relaxes airway muscles. Most short-term side effects like headache and sore throat are well known, but years of daily use can affect bones, skin, eyes, and hormone balance in ways that develop gradually and often go unnoticed without routine monitoring.
Bone Density Loss and Fracture Risk
Inhaled corticosteroids like budesonide interfere with how your body builds and maintains bone. A meta-analysis of over 17,500 patients with COPD found a 27% increase in the relative risk of osteoporotic fractures among those using inhaled corticosteroids. Men in one cohort study faced a twofold elevated risk of vertebral fractures specifically.
The bone loss is measurable year over year. Patients on inhaled corticosteroids lost bone density at roughly 0.91% per year, compared to 0.57% per year in controls. That gap may sound small, but it compounds over a decade of use. The FDA label for Symbicort recommends a bone density scan before starting treatment (particularly for COPD patients) and periodic scans afterward, especially if you have other risk factors like smoking, a family history of osteoporosis, postmenopausal status, poor nutrition, or advanced age.
Growth Reduction in Children
Children using inhaled budesonide grow slightly less than their peers, and the effect is most pronounced in the first year of treatment, averaging about 0.58 cm of reduced growth. In years two and three, the gap narrows to 0.43 cm and 0.33 cm respectively. A long-term follow-up of the landmark CAMP study found that children who used budesonide reached an adult height that was, on average, 1.2 cm shorter than those on placebo. That reduction was similar to what researchers measured after just two years of treatment, suggesting the growth impact happens early and doesn’t worsen much over time.
Interestingly, the effect wasn’t equal across sexes. Girls in the study lost about 1.7 cm of predicted adult height, while the reduction in boys was only 0.3 cm, which wasn’t statistically significant. The FDA recommends routine height monitoring (using a stadiometer) for any child on Symbicort.
Oral Thrush
Oral thrush, a fungal infection that appears as white patches on the tongue and inside the cheeks, is one of the most common local side effects of inhaled corticosteroids. Patients using combination inhalers like Symbicort had more than double the odds of developing oral thrush compared to those on long-acting bronchodilators alone. However, Symbicort’s specific formulation (budesonide/formoterol in a dry powder inhaler) performed better than some alternatives. Patients on Symbicort DPI had 23% lower odds of oral thrush compared to those using fluticasone/salmeterol DPI.
Rinsing your mouth with water and spitting after each dose is the simplest way to reduce this risk. Using a spacer, if your device allows it, also helps keep the medication in your lungs rather than coating your mouth and throat.
Skin Thinning and Bruising
Corticosteroids slow down the production of collagen and other structural proteins in skin. Over time, this leads to thinner, more fragile skin that bruises easily. These changes are estimated to affect roughly half of all patients on long-term inhaled corticosteroids. The risk increases with age, higher doses, and longer duration of use, making elderly patients particularly vulnerable. You might notice bruises appearing from minor bumps that wouldn’t have left a mark before, or skin that tears more easily on your forearms and hands.
Eye Health: Cataracts and Glaucoma
The FDA label for Symbicort warns that long-term use of inhaled corticosteroids may increase the risk of cataracts and glaucoma, and it recommends regular eye exams. However, the actual evidence is more nuanced than the warning suggests. A large meta-analysis of 18 studies found no significant increase in glaucoma incidence among inhaled corticosteroid users. One time-based analysis even suggested a possible protective association, though that finding needs cautious interpretation.
The data on cataracts is less clear-cut, with fewer large meta-analyses focused specifically on inhaled (rather than oral) corticosteroids. The practical takeaway: if you use Symbicort for years, periodic eye exams are worthwhile, especially if you already have risk factors for glaucoma or notice any changes in your vision.
Adrenal Suppression
Your adrenal glands produce cortisol, a hormone essential for managing stress, blood sugar, and immune function. When you inhale budesonide daily, your body may gradually dial down its own cortisol production because it’s receiving a synthetic version. This is called adrenal suppression, and it’s dose-dependent.
A case-control study found that the risk climbs steeply with higher doses. At daily inhaled corticosteroid doses under 600 micrograms, the added risk was modest and not statistically significant after accounting for oral steroid use. At doses between 600 and 1,200 micrograms daily, the risk roughly doubled. Above 1,200 micrograms, the crude risk was over 13 times higher, though adjusting for oral corticosteroid use brought this down considerably. For context, Symbicort’s maximum recommended dose for adults over 12 is 12 puffs per day of the 160/4.5 mcg formulation, which delivers 1,920 mcg of budesonide at the upper limit.
Adrenal suppression rarely causes noticeable symptoms during normal daily life. The danger surfaces during physical stress like surgery, serious illness, or injury, when your body needs a cortisol surge it can no longer produce on its own. This is one reason you should never abruptly stop a long-term inhaled corticosteroid without medical guidance.
What Monitoring Looks Like
If you’ve been on Symbicort for a year or more, a few periodic checks can catch problems early before they cause symptoms:
- Bone density scans are recommended before starting treatment for COPD patients and periodically afterward, particularly if you’re older, postmenopausal, or have other bone loss risk factors.
- Eye exams should be part of your routine, especially if you have a history of elevated eye pressure, glaucoma, or cataracts.
- Oral cavity checks at dental or medical visits can catch thrush or other fungal infections early.
- Height measurements for children should be tracked at regular intervals using consistent methods.
- Pneumonia awareness matters for COPD patients, since inhaled corticosteroids can increase susceptibility to lung infections.
Most of these side effects are dose-dependent, meaning the lowest effective dose carries the least risk. If you’ve been stable on Symbicort for a long stretch, it’s reasonable to ask whether your current dose is still the right one or whether stepping down is an option.