Necrotic and ulcerative lesions of the oral mucous membranes occurred in five patients with chronic renal failure. All were receiving a solution of 9.8% sodium citrate and 14% citric acid (Shohl solution) orally to alleviate metabolic acidosis. The lesions were reproduced experimentally in rabbits and were shown to be due to a direct primary irritant effect of the Shohl solution. Such lesions probably occur more commonly than is generally known. It is suggested that Shohl solution be diluted when used by patients who have difficulty swallowing or poor oral hygiene.
Newell GB, Stone OJ. Irritant Contact Stomatitis in Chronic Renal Failure. Arch Dermatol. 1974;109(1):53-55. doi:10.1001/archderm.1974.01630010033006