Objective To quantify the healthcare expenditures associated with potential oral glucocorticoid (OGC)-related adverse events (AEs) in patients with giant cell arteritis (GCA). Methods Patients with GCA and≥ 1 OGC prescription fill between 2009 and 2014 were identified from the MarketScan Commercial and Medicare Supplemental claims databases. Patients were stratified into four groups based on cumulative OGC dose (> 0 to≤ 2607 mg,> 2607 to≤ 4800 mg,> 4800 to≤ 7200 mg, and> 7200 mg) during the 1-year follow-up period; incidence of potential AEs and AE-related direct healthcare costs in USD were assessed. Association between the log of cumulative OGC dose and AE-related direct healthcare costs was evaluated, adjusting for baseline characteristics. Results Of 1602 patients with GCA included, 69% were women; the mean age was 73 years. The mean cumulative OGC dose was 5806 mg during the 1-year follow-up; most exposure occurred in the first 6 months. The proportion of patients with potential OGC-related AEs was 36.5% overall and increased as cumulative dose increased (30.7%–45.3% across dose groups). Unadjusted mean AE-related costs for patients with an AE was USD 12,818.Inthemultivariablemodelincludingallpatients,increasingOGCdosewasassociatedwithincreasingAE-relatedhealthcarecosts(costratio,1.3895%CI,1.16–1.64per1-unitincreaseinlogofcumulativeOGCdoseP<0.001).Mean(median)-predictedAEcostsforthedosegroupswereUSD 4389 (2749)for>0to≤2607mg,USD 5176 (3009)for>2607to≤4800mg,USD 5576 (3633)for>4800to≤7200mg,andUSD 6609 (4447)for>7200mg.ConclusionInpatientswithGCA,OGC-relatedAEsincreasedwithincreasingcumulativeOGCdose,resultinginincreasedhealthcarecosts.TheseresultshighlighttheneedforefficacioustherapiesthatreducetheexposuretoandpotentialrisksassociatedwithOGCs.