When your veterinary surgeon suspects Cushing’s syndrome, they will perform blood tests to confirm the diagnosis. It is also recommended that blood tests are carried out to assess the overall health of your dog.
The cortisol concentration in the blood fluctuates greatly throughout the day in both healthy dogs and dogs with Cushing’s syndrome. It is for this reason diagnosis cannot be confirmed by just one measurement of cortisol. The two tests most commonly used to confirm diagnosis are the ACTH stimulation test and the low-dose dexamethasone suppression test. It may be necessary to perform both tests.