Amylase isoenzymes are a test that separates and measures the relative proportions of the two main types of amylase enzyme in serum: pancreatic amylase (P-type) and salivary amylase (S-type). Although both break down starch, they are produced by different tissues and have different electrical properties. This separation allows for the determination of whether an elevated total amylase level is due to pancreatic injury (in the case of elevated P-type) or to other causes such as diseases of the salivary glands, ovaries, lungs, or certain tumors (in the case of elevated S-type).