Disease-modifying treatments are designed to prevent exacerbations in multiple sclerosis (MS). To date, few studies have examined the relationship between disease activity and treatment adherence in MS. The primary aim of this study was to examine the association between disease activity (e.g., annualized relapse rates), medication adherence, and appointment adherence in relapsing-remitting MS. Retrospective exacerbation and appointment data were collected and used to predict prospective medication adherence. Results indicated that patients with higher annualized relapse rates missed fewer doses of medication and were less likely to miss appointments. Conversely, patients with relatively stable disease were more likely to demonstrate poor medication adherence and poor appointment adherence. Patients who missed more appointments also missed more doses of their disease modifying medication. Future studies may wish to examine clinical methods designed to improve immunotherapy adherence among patients who are in relatively symptom-free stages of relapsing-remitting MS.