Pheochromocytoma A pheochromocytoma is a tumor of the adrenal medulla, which overproduces adrenaline (epinephrine) and noradrenaline (norepinephrine), leading to a high blood pressure, which may be continuous or intermittent. There may be episodes of a fast heartbeat with palpitations, weight loss, sweats, blanching or flushing, headache and chest pain. Although fewer than % of all people with high blood pressure harbor this tumor, under certain circumstances, testing is important to evaluate for this disorder, due to the potential fatality from “crisis” consisting of severe hypertension and heart arrhythmia. Up to 25% of pheochromocytomas may be familial, occurring more frequently in people with rare hereditary disorders, including multiple endocrine neoplasia type 2 (MEN 2), Von Hippel Lindau disease and Neurofibromatosis. Genetic testing is available for these disorders and for family members of affected patients.