Felinine synthesis starts in the liver through a condensation reaction of glutathione and isopentenyl pyrophosphate to form 3-methylbutanolglutathionine (3-MBG).

[5] Cauxin specifically works by hydrolyzing the dipeptide (felinylglycine) in MBCG to increase the concentration of urinary felinine.

[6] The leftover MBCG is converted to felinine and secreted into the cells where it is acetylated and transported to fecal material.

[5] Urine of domestic cats may contain a series of felinine-containing compounds including free felinine, acetylfelinine, felinylglycine and 3-MBG.

[9] Felinine excretion is regulated by levels of testosterone, and so its concentration is dependent on the sex and age of the cat.

This is most likely caused by the presence of arginine, which is believed to inhibit synthesis of MBG, which decreases felinine excretion.