To study efficacy and safety of cholinergic therapy in patients with Alzheimer's disease or combined Alzheimer's and vascular dementia and marked somatic pathology, 30 patients, aged from 54-85 years, with mild or moderate dementia have been studied. Patients were treated with rivastigmine (exelon) in dosage 3-12 mg daily during 3 months. The safety of the drug for patients with comorbid somatic pathology has been shown: during the treatment no severe aversive effects or strengthening of diseases of visceral organs were observed. The improvement of global clinical state as well as reduction of cognitive and behavioral disorders indicate the high effectiveness of exelon. The recommendations allowing to improve the tolerability of treatment with exelon of patients with comorbid pathology of visceral organs are worked out.