N-alpha-Acetylarginine is one of the guanidino compounds found elevated in the serum of a hemodialyzed renal insufficient (uremic) pediatric population.

H-Arg-4MβNA (H-Arg-4MbNA) is a peptide that serves as a substrate for cathepsin H. The enzyme activity is often detected in gel electrophoresis.

Meclocycline (INN) is a tetracycline antibiotic. It is used topically (i.e. for skin infections) as it is totally insoluble in water and may cause liver and kidney damage if given systemically.