FIELD: medicine, peptides, pharmacy. SUBSTANCE: invention proposes biologically active tetrapeptide lysyl-glutamyl-aspartyl-alanine of the general formula: Lys-Glu-Asp-Ala stimulating functional activity of hepatocytes and pharmacological agent containing effective amount of tetra-peptide of the formula Lys-Glu-Asp-Ala or its salts as an active component that can be used for parenteral, intranasal and oral administration. Method of stimulation of functional activity of hepatocytes involves curative administration to patient the pharmacological agent in doses 0.01-100 mcg/kg of body mass for at least once per a day for period that is necessary for therapeutic effect attainment. Agent stimulating functional activity of hepatocytes recoveries synthesis of nonspecific proteins, normalizes metabolism, activates processes of proliferation and differentiation of liver cells. Invention can be used as an agent stimulating functional activity of hepatocytes for prophylaxis and treatment of patients with diseases and damages of liver. EFFECT: enhanced effectiveness of agent, improved method of use. 10 cl, 3 dwg, 5 tbl, 7 ex
