**Abstract**

Uremic toxins are a diverse group of substances that contribute significantly to the high cardiovascular disease burden in chronic kidney disease (CKD). When glomerular filtration begins to decrease, a disorder in the intestinal microflora known as dysbiosis occurs; this produces alterations in metabolic activities and decreased excretion of waste products. These substances have been identified and classified, accordingly to molecular weight and clearance. Biological and clinical effects have also been identified. These substances have different effects depending on the tissue or cell where they accumulate. The recommendations for a low-protein diet in predialysis patients and the use of probiotics, prebiotics, and synbiotics added to the removal techniques in hemodialysis can help reduce the inflammatory effects and those associated with mortality.

**Keywords:** uremic toxins, chronic kidney disease, dysbiosis, hemodialysis, cardiovascular mortality
