Discontinuation of antimalarial drugs in systemic lupus erythematosus

Abstract

Objective: To assess the reasons for and timing of discontinuation of antimalarial drugs, principally hydroxychloroquine (HCQ), in systemic lupus erythematosus (SLE).

Methods: A lupus database was reviewed to identify antimalarial use from inception to April 1996. Reasons for drug discontinuation were assessed by medical record review.

Results: Of 224 patients with SLE, 156 (70%) had received antimalarials. The 156 users received 203 courses of antimalarials, of which 197 (97%) were for HCQ. The average duration of use was 6.9 years/patient. Antimalarials were discontinued at least once in 62 patients. When only the first course of use was considered, 67, 50, and 38% of patients continued to receive antimalarials at 5, 10, and 15 years, respectively (for all courses, the rates were 82, 66, and 52%, respectively). Reasons for discontinuation were disease remission in 26 (42%), side effects in 18 (29%), noncompliance in 9 (15%), lack of efficacy in 5 (8%), and miscellaneous causes such as pregnancy/surgery in 4 (6%). When all courses were considered, 20 subjects were withdrawn for side effects, including gastrointestinal in 11; headache and dizziness, and nonretinal eye problem in 2 each; and hearing loss and rash in one each. Two developed HCQ myopathy (1.9 cases/1000 patient-years of HCQ therapy; 95% CI 0.2, 7.0). One developed HCQ retinopathy after 6 years at a dose of 6.5 mg/kg/day (0.95 cases/1000 patient-years of HCQ; 95% CI 0.0, 5.5). Among patients who had received HCQ for at least 6 years, 1.3% developed retinopathy (95% CI 0.03, 7.0%).

Conclusion: HCQ is well tolerated in SLE. However, ophthalmologic testing remains essential, as retinopathy does occur, albeit rarely.