Question: Can Cushing's syndrome or Cushing's disease cause severe headaches?
 
Answer: Headaches in a patient with Cushing's Disease (a pituitary tumor) are usually related to the presence of the tumor. A headache may occur with either a microadenoma or macroadenoma. A microadenoma is < 10 mm and a macroadenoma is > 10 mm. The high cortisol levels per se are not known to cause headaches.