Intestinal Chelators, Sorbants, and Gut-Derived Uremic Toxins

Toxins (Basel). 2021 Jan 26;13(2):91. doi: 10.3390/toxins13020091.


Chronic kidney disease (CKD) is a highly prevalent condition and is associated with a high comorbidity burden, polymedication, and a high mortality rate. A number of conventional and nonconventional risk factors for comorbidities and mortality in CKD have been identified. Among the nonconventional risk factors, uremic toxins are valuable therapeutic targets. The fact that some uremic toxins are gut-derived suggests that intestinal chelators might have a therapeutic effect. The phosphate binders used to prevent hyperphosphatemia in hemodialysis patients act by complexing inorganic phosphate in the gastrointestinal tract but might conceivably have a nonspecific action on gut-derived uremic toxins. Since phosphorous is a major nutrient for the survival and reproduction of bacteria, changes in its intestinal concentration may impact the gut microbiota's activity and composition. Furthermore, AST-120 is an orally administered activated charcoal adsorbent that is widely used in Asian countries to specifically decrease uremic toxin levels. In this narrative review, we examine the latest data on the use of oral nonspecific and specific intestinal chelators to reduce levels of gut-derived uremic toxins.

Keywords: chronic kidney disease; phosphate binders; uremic toxins.

Publication types

  • Review

MeSH terms

  • Adsorption
  • Animals
  • Bacteria / metabolism*
  • Carbon / adverse effects
  • Carbon / therapeutic use
  • Charcoal / adverse effects
  • Charcoal / therapeutic use*
  • Chelating Agents / adverse effects
  • Chelating Agents / therapeutic use*
  • Gastrointestinal Microbiome*
  • Humans
  • Intestines / microbiology*
  • Oxides / adverse effects
  • Oxides / therapeutic use
  • Phosphorus / metabolism*
  • Renal Insufficiency, Chronic / diagnosis
  • Renal Insufficiency, Chronic / metabolism
  • Renal Insufficiency, Chronic / microbiology
  • Renal Insufficiency, Chronic / therapy*
  • Toxins, Biological / metabolism*
  • Treatment Outcome


  • Chelating Agents
  • Oxides
  • Toxins, Biological
  • Charcoal
  • Phosphorus
  • Carbon
  • AST 120