Dementia is a progressive neurodegenerative disorder characterized by cognitive decline, impaired memory, and functional impairment. Pharmacotherapy plays a cru- cial role in the management of dementia, aiming to alleviate symptoms, slow down disease progression, and improve patients' quality of life. The theoretical part of the diploma thesis will scrutinize the classification and characteristics of each type of dementia, epidemiology and risk factors related to the disease. The practical part will monitor at least 42 patients with dementia from the Abolfazl Charity Sanitarium in Hamedan, Iran, supervised by Dr. Abbas Gharegozlu. To assess the cognitive function of patients the Mini-Mental State Examination (MMSE) will be analysed at three different time points over one year. The efficacy of pharmacotherapy, possible side effects related to each drug, and other factors that might contribute to the development of the disease will be elaborated on. The main aim will be to identify any differential effects of the treatment regimens on the progression of cognitive decline and functional impairment.