Prescription patterns of anti-rheumatic drugs in patients with rheumatoid arthritis at a community pharmacy near a secondary-care hospital in South Korea

Abstract

Rheumatoid arthritis (RA), one of the most common forms of inflammatory disease, induces chronic inflammation of the joints and various organs. Therapy with disease-modifying anti-rheumatic drugs (DMARDs) should be initiated immediately after a diagnosis of RA because the early initiation of DMARDs can prevent joint damage in a large proportion of RA patients. The aims of this study were to analyze the prescription patterns of RA medication in Korean patients visiting a community pharmacy and to examine drug-drug interactions (DDIs) between DMARDs and concomitant medications. A retrospective study was conducted with RA patients visiting the community pharmacy, located at the southern region of South Korea, between January and February 2015. Data were collected through the review of patients’ prescriptions. During the study period, 931 were diagnosed with RA. Methotrexate (MTX), hydroxychloroquine (HCQ), leflunomide (LEF), tacrolimus (TAC), and sulfasalazine (SUL) were prescribed to 703 (75.51%), 387 (41.57%), 303 (32.55%), 131 (14.07%), and 83 (8.92%) patients, respectively. The most commonly prescribed combination was DMARDs+glucocorticoids (GCs) (40.79%). MTX and TAC showed drug interactions with non-steroidal anti-inflammatory drugs (NSAIDs) and proton pump inhibitors (PPIs), but significant DDIs between HCQ or LEF and co-administered drugs were not found. MTX was the most commonly prescribed DMARD for both monotherapy and in combination with other DMARDs. The commonly prescribed DMARDs (i.e., MTX and TAC) were demonstrated to have DDIs with NSAIDs and PPIs. Therefore, the co-administration should be carefully monitored, especially in elderly patients with polypharmacy.