Obesity that results in various metabolic disorders is one of the central concerns of modern healthcare system. Only 4% to 5% of patients with metabolic syndrome achieve favorable outcomes without any additional pharmacotherapy. Therefore, many patients require weight-loss drugs in addition to non-pharmacological treatments. The endocannabinoid system and the drugs that affect its functions receive a widespread attention of medical society due to its effects on behavioral and cerebral functions and its potential use as a therapeutic “target” in various peripheral and neurological psychiatric disorders. Among known to date cannabinoid receptors, type 1 receptors play a role in the development of obesity. It was demonstrated that the blockade of these receptors in the hypothalamus reduces appetite, inhibits adipocyte activation in peripheral tissues, prevents lipogenesis, and increases the level of adiponectin. The result is the decreased levels of atherogenic lipoproteins and improved insulin resistance. This article addresses the results of fundamental and clinical studies on Dietressa, a drug composed of affine-purified antibodies to cannabinoid receptor 1. Case report of a patient with obesity that analyzes pharmaceutical and non-pharmaceutical treatment approaches is described.KEYWORDS: obesity, metabolic syndrome, diet, endocannabinoid system, cannabinoids, cannabinoid receptors, affine-purified antibodies.FOR CITATION: Dudareva V.A., Maksimov M.L., Djadikova I.G. et al. Role of endocannabinoid system in the pathogenesis of obesity: how can we help a patient? From theory to practice. Russian Medical Inquiry. 2020;4(6):382–389. DOI: 10.32364/2587-6821-2020-4-6-382-389.