Excess of cortisol causes:
Conn's syndrome
Cushing's syndrome
Acromegaly
Diabetes insipidus
When corticotropin and glucocorticoids are secreted in excessive amounts for long periods, as occurs in the endocrine condition called Cushing’s syndrome.
Hypersecretion by the adrenal cortex causes a complex cascade of hormone effects called Cushing’s syndrome. Many of the abnormalities of Cushing’s syndrome can be ascribed to abnormal amounts of cortisol, but excess secretion of androgens may also cause important effects.
Reference: GUYTON AND HALL TEXTBOOK OF MEDICAL PHYSIOLOGY, THIRTEENTH EDITION(INTERNATIONAL EDITION ) page no 870,979