*11.6.3. Hydrolysis*

Drugs containing ester functions (R1COOR2) such as procaine are hydrolyzed by a variety of non-specific esterases in liver, and plasma while drugs with amide bonds are hydrolyzed by amidases in the liver. The polypeptide drugs such as insulin and growth hormones are hydrolyzed by peptidases in the plasma and erythrocytes. The metabolites resulting from hydrolysis reactions are subjected to phase II biotransformation reactions before excretion in the bile or urine.
