Pheochromocytoma is a catecholamine secreting tumour that arises from the chromaffin cells of the sympathetic nervous system in the adrenal medulla and the sympathetic chain; however, it may arise anywhere in the body. Patients present with a variety of symptoms which reflect excessive secretion of catecholamines (norepinephrine, epinephrine, or dopamine) into the circulation. The released catecholamines cause significant hypertension, often severe and refractory to conventional treatment. The greatest frequency occurs in the fourth and fifth decade of life, with a slightly higher female preponderance. About 90% of pheochromocytomas occur sporadically and are benign. Around 10% of cases occur in children or adolescents.