Obesity is one of the pathologies with ever-increasing prevalence in modern societies. Its occurrence is strongly associated with increased risk of developing diabetes mellitus, atherosclerosis, hypertension, stroke, heart and respiratory failure, breast, prostate and gut cancer, gall stones, arthropathy. Obesity is common in Polish population. Obesity treatment is difficult and frustrating. It consists of several parts like diet, increased physical activity, lifestyle changes, drug therapy and surgery. However, obesity treatment is very often a failure, mostly because of discouraging long-term results and the necessity of intensive patient's involvement in the therapy. For many patients and doctors weight-decreasing agents look promising. The groups of anti-obesity drugs are presented in the article, with special reference to serotoninergic agents and intestinal lipase inhibitors. The prospects for new anti-obesity agents are discussed. Nevertheless, despite intensive research on obesity, we are still waiting for the development of an effective and safe drugs helping lose weight.