Adrenaline is particularly useful in making the diagnosis in patients with small adrenal phaeochromocytomas since the enzyme that converts noradrenaline to adrenaline is glucocorticoid dependent; hence, with the centripetal blood flow in the adrenal, the medulla is exposed to high levels of cortisol.
A variety of pharmacological tests have been developed in an attempt to improve the diagnosis of patients with phaeochromocytomas. With advances in biochemical diagnosis, however, these have nearly all been discarded.
