Glucocorticoids (GC) are considered first-line therapy for treating sarcoidosis, but there are few data about the adverse consequences of GC. Although there are several steroid-sparing medications available for treatment, a large proportion of patients are treated with prolonged courses of GC. The toxicities of GC in sarcoidosis populations have not been carefully evaluated. We performed a retrospective cohort study of all newly diagnosed sarcoidosis patients who had the entirety of their medical care in a single health system. We analyzed the time to development of a composite toxicity end-point, including diabetes, hypertension, weight gain, hyperlipidemia, low bone density and ocular complications of GC using Cox proportional hazards analysis. One hundred and five patients were ever treated with GC, whereas 49 were not treated during a median follow-up of 101 months. GC-treated patients developed 1.3 ± 1.1 toxicities during therapy, versus 0.6 ± 1.0 in the non-treated group. After adjustment for age, gender, race and preexisting conditions, the hazard ratio for ever-treated patients was 2.37 (1.34–4.17) for the composite end-point. Age and the presence of preexisting conditions also were associated with reaching the end-point. Similar effects were seen when analyzed for cumulative GC dose and for duration of GC use. For individual end-points, weight gain (HR 2.04) and new hypertension (HR 3.36) were associated with any use of GC. Our data suggest that GC are associated with clinically important toxicities in sarcoidosis patients, associated with both the cumulative dose and duration of treatment. •Standard therapy of sarcoidosis includes steroids, often in prolonged courses.•Long-term steroids for sarcoidosis are associated with significant comorbidity.•Steroid therapy in sarcoidosis needs to be re-evaluated and minimized when possible.