Amylase is a digestive enzyme produced primarily by the pancreas and salivary glands. It catalyses the breakdown of starch and glycogen into simpler sugars. Normally only small amounts circulate in the bloodstream. When the pancreas is inflamed or damaged, amylase leaks into the bloodstream in large quantities, causing serum amylase to rise sharply.
Amylase rises within 2–6 hours of acute pancreatitis onset and returns to normal within 3–5 days. Lipase is now generally preferred for pancreatitis diagnosis because it remains elevated longer and is more pancreas-specific. Amylase also originates from the salivary glands, meaning elevations can be caused by parotid gland disorders rather than pancreatic disease.
FAQs
Is amylase or lipase better for diagnosing pancreatitis?
Lipase is now generally preferred because it is more specific to the pancreas, remains elevated longer, and is not raised by salivary gland disorders. However, both tests together improve diagnostic accuracy.
Can amylase be elevated without pancreatitis?
Yes — salivary gland disorders, kidney impairment, macroamylasaemia, and certain medications can all raise amylase without pancreatitis. Mildly elevated amylase without abdominal pain is often not caused by pancreatitis.
How quickly does amylase rise in acute pancreatitis?
Amylase rises within 2–6 hours of onset, peaks around 24 hours, and returns to normal within 3–5 days. Lipase is more useful in late presentations where amylase may already be normalising.
What is macroamylasaemia?
Macroamylasaemia is a benign condition where amylase binds to immunoglobulins forming large complexes the kidneys cannot excrete, causing persistently elevated serum amylase. It requires no treatment but should be recognised to avoid unnecessary investigation.
