Abstract Introduction Colchicine is recommended first line in the management of idiopathic recurrent pericarditis (IRP) at low doses (0.5 - 1 mg/24h). In cases refractory to low dose colchicine, corticosteroid use is common, despite an increased risk of disease recurrence and the risk of complications resulting from corticosteroid dependence. Biologic agents that block interleukin-1, anakinra and rilonacept, are highly effective in IRP, but their use is limited by expertise and cost. Colchicine uptitration is recommended by consensus international guidance in familial Mediterranean fever, a disease characterised by recurrent serositis, and, hence, offers an accessible steroid sparing approach to the management of treatment-refractory idiopathic recurrent pericarditis Purpose To explore the safety and feasibility of colchicine uptitration in patients with IRP refractory to low dose colchicine (0.5-1 mg/24h). Methods Retrospective review of electronic medical records of all patients with IRP and familial Mediterranean fever reviewed at a tertiary centre 2013-2023. Treatment-refractory IRP cases were defined as active disease despite colchicine 1mg/24h or disease requiring other prophylactic drugs, and corticosteroid dependence as daily corticosteroid use for 6 months. Results Of 121 IRP cases, 77 (63.6%) were treatment refractory at first review. Median follow up was 24 months (IQR 6 – 36). Corticosteroid dependence complicated 34/77 (44.2%) cases. Of treatment-refractory cases without corticosteroid dependence, 42/43 (97.7%) were treated with colchicine uptitration and 4/43 (9.3%) with anti-interleukin-1 biologic(s); none became corticosteroid dependent. Of corticosteroid dependent cases, 30/34 (88.2%) were treated with colchicine uptitration and 13/34 (38.2%) with anti-interleukin-1 biologic(s). Corticosteroids were fully discontinued in 25/34 (73.5%): 8/25 (32.0%) weaned with colchicine uptitration alone, 14/25 (56.0%) with anti-interleukin-1 biologic(s) and 3/21 (14.3%) with azathioprine. Median corticosteroid duration was 17.5 months (IQR 13 - 44.25) and corticosteroid toxicity occurred in 8/34 (23.5%). Among the 76/77 cases (98.7%) treated with colchicine (median maintenance dose 2 mg/24h (IQR 1.5-2)), permanent discontinuation was uncommon (3/76, 3.9%) and due to gastrointestinal symptoms. Self-limiting liver transaminase elevation was common (29/76, 38.2%) but did not lead to discontinuation in any case. The prevalence of liver transaminase elevation among patients with familial Mediterranean fever on life long colchicine was 181/568 (31.9%). Conclusions In this treatment-refractory pericarditis cohort, colchicine uptitration enabled avoidance of new corticosteroid dependence, facilitated corticosteroid discontinuation and was well tolerated. This contrasts with the frequent toxicity seen with prolonged corticosteroid use and offers an accessible steroid sparing approach to IRP management that warrants prospective investigation.