Alkaline phosphatase (ALP)

Alkaline phosphatase, or ALP, is an enzyme found in the liver, bone, intestine and other tissues, and its blood level is a routine marker on a veterinary chemistry panel.

Enzymes are proteins that speed chemical reactions, and ALP removes phosphate groups from other molecules in an alkaline environment. In dogs, most circulating ALP comes from the liver and bile ducts, with contributions from growing bone in puppies and a form induced by steroid hormones. A veterinarian reads the value alongside other liver markers such as ALT and bilirubin, because a rise in ALP alone is common, often mild and can reflect many causes, from medications to age-related changes.

Pet owners meet this term on bloodwork printouts and in conversations about monitoring. Published veterinary studies of CBD in dogs have reported increases in ALP in some animals, and researchers have not yet settled whether this reflects liver stress or a benign enzyme induction. Anyone whose dog is on a long-term medication or supplement should discuss periodic blood monitoring with a veterinarian.