Background Patients with rheumatic diseases can experience multiple drug-related problems (DRPs) along their patient journey. 1 Insight into patients’ experience of DRPs over time might aid in timely identifying and preventing DRPs. 2,3 Objectives To longitudinally identify DRPs experienced by patients with rheumatic diseases. Methods A prospective observational study was conducted in a Dutch outpatient pharmacy. Adult patients with rheumatic diseases that were prescribed medication by a rheumatologist were questioned about experienced DRPs by telephone 4 times in 8 weeks using a structured interview-guide. Unique DRPs (i.e. DRPs not reported in earlier interviews by individuals) were categorized using a classification for patient-reported DRPs and analysed descriptively. Results In total, 52 participants (median age 68 years (interquartile range (IQR) 62-74), 52% male) completed 192 interviews with 45 (87%) participants completing all 4 interviews. The majority of patients (65%) were diagnosed with rheumatoid arthritis. Patients reported a median number of 3 (IQR 2-5) unique DRPs during interview 1. In subsequent interviews, patients reported median numbers of 1 (IQR 0-2), 1 (IQR 0-2) and 0 (IQR 0-1) unique DRPs for interview 2 to 4 respectively. Participants reported a median number of 5 (IQR 3-9) unique DRPs over all completed interviews. Unique patient-reported DRPs were most frequently categorized into (suspected) side effects (28%), medication management (e.g. medication administering or adherence) (26%), medication concerns (e.g. concerns regarding long-term side-effects or effectiveness) (19%) and medication effectiveness (17%). Conclusion Patients with rheumatic diseases experience various DRPs over time. These patients might benefit from continuous support during their patient journey. References [1]Huiskes, V. J. B., Burger, D. M., Van Den Ende, C. H. M. & Van Den Bemt, B. J. F. Effectiveness of medication review: A systematic review and meta-analysis of randomized controlled trials. BMC Fam. Pract. 18 , (2017). [2]Kari, H., Kortejärvi, H., Airaksinen, M. & Laaksonen, R. Patient involvement is essential in identifying drug-related problems. Br. J. Clin. Pharmacol. 84 , 2048–2058 (2018). [3]Kwint, H. F., Faber, A., Gussekloo, J. & Bouvy, M. L. The contribution of patient interviews to the identification of drug-related problems in home medication review. J. Clin. Pharm. Ther. 37 , 674–680 (2012). Acknowledgements The authors wish to thank the patients that participated in this study and the pharmacy technicians that conducted the structured interviews. Disclosure of Interests None declared