Background: Rivastigmine is used for symptomatic treatment of mild-to-moderately severe Alzheimer's Dementia (AD). We investigated the frequency of and reasons for rivastigmine discontinuation in clinical practice and possible predictive factors for discontinuation within the first six months after starting therapy., Methods: A retrospective cohort study was performed in rivastigmine users, who started therapy in a naturalistic setting. A nurse supported a part of the studied cohort, as this was introduced during the study period. Reasons for discontinuation were investigated, including therapy discontinuation if the Maximum Achieved Dose (MAD) was below 6 mg daily. Predictors of discontinuation within the first half year were investigated by logistic regression analysis., Results: Baseline Mini-Mental-State-Examination (MMSE) of included patients (n = 154) was 20.1, mean age was 78.4 years and 70% was female. Within 6 months, 61 users (39.6%) discontinued therapy, primarily (59.0%) for adverse events. Thereafter, the main reason for discontinuation was non-response according to clinimetrics. A MAD during the titration phase of 1.5-4.5 mg/day and absence of nurse support are significantly related to discontinuation within 6 months., Conclusions: Rivastigmine is primarily discontinued within the first six months for intolerable adverse events and thereafter mainly for ongoing deterioration. A MAD of 1.5-4.5 mg/day and the absence of nurse support are independently related to discontinuation of rivastigmine within the initial 6 months., (Copyright (c) 2005 John Wiley & Sons, Ltd.)