Aristolochic acid (AA-I), a naturally occurring nitrophenanthrene carboxylic acid, commonly found in the plant family Aristolochiaceae, that are used in traditional Chinese medicine. Aristolochic acid exhibits nephrotoxic, carcinogenic, and mutagenic activities and can cause aristolochic acid nephropathy, and urothelial malignancies. The FDA has issued a strong warning to consumers to avoid herbs containing the chemical aristolochic acid. The mechanisms underlying AA-I toxicity in the kidneys are poorly understood. However, was found a protein α-actinin-4 that is inhibited by AA-I, resulting in kidney disease.

p-Chlorobenzoic acid is a major metabolite of analgesic agent zomepirac sodium in rat (present as conjugates) and mouse and a minor one in monkey and man. It is a metabolite of antidepressant Lofepramine hydrochloride, and anxiolytic and a muscle relaxant Chlormezanone too. Sodium salt of p-Chlorobenzoic acid is used as a preservative. p-Chlorobenzoic acid may prove useful clinically to prevent and reverse the accumulation of toxic levels of acyl- and arylCoA esters. If the hepatic damage in Reye’s Syndrome is due to the dead-end formation of the CoA esters of acyl- and aryl-CoA esters, then p-chlorobenzoic acid may block their formation, thereby relieving the inhibitions of gluconeogenesis and urea synthesis and preventing some of the damage to the liver.