Charcoal for the management of pruritus and uremic toxins in patients with chronic kidney disease

Abstract

Purpose of the review: Pruritus is an important, prevalent but often neglected symptom in patients with advanced CKD or on dialysis,. This review addresses the use of activated charcoal and its analogs in the treatment of uremic pruritus, which can be a marker of uremic toxicity. Recent findings: When common causes are corrected and dialysis efficiency is optimized, pruritus is mainly ascribed to the retention of middle and protein-bound molecules, of which indoxyl sulfate and p-Cresyl sulfate are the best studied. While hemodialysis and hemodiafiltration are of limited use, activated charcoal and its analogs offer interesting alternatives. Oral preparations are associated with symptom improvement and a better metabolic pattern, probably via a combination of absorption and modification of the intestinal microbiota. Large studies, in well-phenotyped populations, are needed. Hemoperfusion, commonly used in poisoning pathologies, could be an interesting alternative in hemodialysis patients. The treatment has proved promising in some preliminary and small studies; more research is now needed to test its validity. Summary: Oral activated charcoal and hemoperfusion can be proposed to patients with severe refractory pruritus based on positive, albeit scattered evidence. They also contribute to reducing uremic toxins. Research on their implementation associated with well-established treatments is needed to understand whether they can be used as "uremic detoxifiers".

CKD-Associated Pruritus: New Insights Into Diagnosis, Pathogenesis, and Management

“…summarize existing data and conclude that, although the evidence is limited, both oral activated charcoal and HD or hemoperfusion with an activated charcoal cartridge may have a role in the treatment of CKDaP. 81 …”

“…80 In a recent review, Cupisti et al summarize existing data and conclude that, although the evidence is limited, both oral activated charcoal and HD or hemoperfusion with an activated charcoal cartridge may have a role in the treatment of CKDaP. 81 Hyperparathyroidism and high calcium, magnesium, and phosphorus levels have been associated with CKD-aP, and a few small studies suggest that decreasing the levels of these potential pruritogens may decrease itching. 61,82 A prospective, uncontrolled study of 37 dialysis patients with secondary hyperparathyroidism (mean PTH level, 1473 pg/ml), of which 22 had pruritus, found that parathyroidectomy significantly decreased itching.…”

Effects of Uremic Clearance Granules in Uremic Pruritus: A Meta-Analysis

“…Systemic inflammation caused by pruritogens (accumulated uremic toxins, histamines, and proinflammatory cytokines) and the imbalance of the opioid system are considered to be possible pathogenesis of UP [5,50]. The accumulated uremic toxins can destroy the intestinal barrier integrity, cause dysbiosis of the gut, and progressive kidney damage [50,51]. Toxins, including mineral products and uremic toxins, were proposed as pruritogens [4].…”

Chronic Kidney Disease-Associated Pruritus

“…Kt/V has been found to be inversely related to CKD-aP [ 40 ]. Higher dialysis improves the prevalence and intensity of pruritus in hemodialyzed patients [ 65 ]. Neutral macroporous resin hemoperfusion (HP) was used in a study to treat maintenance hemodialysis patients (MHD) with refractory uremic pruritus.…”

“…Oral charcoal is most frequently associated with side effects such as appetite loss, nausea, constipation, and gastrointestinal discomfort [ 67 ]. In a study, cholestyramine, a nonabsorbable anion-exchange resin, which binds organic acids intraluminally, has been found effective in relieving CKD-aP [ 65 ].…”