The efficacy of mirtazapine in agitated patients with Alzheimer’s disease: A 12-week open-label pilot study

Agitation is one of the most devastating behavioral symptoms in demented patients but there is little evidence about effective and safe pharmacotherapy. We aimed to determine the effectiveness and safety of mirtazapine in treatment of agitated patients with Alzheimer's disease (AD). The consecutive patients with AD who have significant agitation were assigned to a 12-week open-label, prospective study. Patients received mirtazapine 15-30 mg/day. The changes in Cohen-Mansfield Agitation Inventory-Short form (CMAI-SF) scores were primary outcome measurement. The change in Clinical Global Impression-Severity scale (CGI-S) scores and tolerability-safety profile were the secondary efficacy variables. Thirteen of 16 (81.25%) patients completed the study. There was a significant reduction in CMAI-SF and CGI-S between the pre- and post-treatment with mirtzapaine (p < 0.001). The mean baseline score was 26.54 ( +/- 5.4) and mean reduction was 10.6 ( +/- 7.5) in CMAI-SF. There was no significant side effect and cognitive deterioration. The results of this open-label pilot study suggest that mirtazapine may be an effective choice for treatment of agitated patients with AD.