Medications may not work effectively if patients do not take them. Recently, direct oral anticoagulants (DOACs) instead of warfarin are being more frequently utilized for the treatment of non-valvular atrial fibrillation (NVAF) to prevent thromboembolism events. However, nonadherence to medication may worsen the prognosis in NVAF patients despite the proven efficacy of DOACs for stroke prevention. The obstacles to taking DOACs vary among individual patients. We conducted a randomized controlled trial to evaluate the effect of pharmacist-led educational intervention on medication adherence assessed by electronic monitoring in patients with NVAF who were treated with once-daily DOACs or twice-daily DOACs. From the results, we would like to discuss the individualization of medication counselling in community medicine.