Conn's syndrome, or primary hyperaldosteronism, is a disorder caused by excess production of aldosterone, a hormone produced in the adrenal glands that helps control the amounts of sodium and potassium in the blood. Symptoms of Conn's syndrome include high blood pressure, headache, tiredness, excessive urination (often during the night), and a decrease in potassium levels in the blood.

The most common cause of Conn's syndrome is an aldosterone-producing tumor of the adrenal gland. Women between the ages of 30 and 50 are at highest risk for developing Conn's syndrome.

If the tumor causing Conn's syndrome can be found, it is removed through surgery. If high blood pressure continues after surgery, or if surgery is not done, treatment may include medicines to block aldosterone, a diet low in salt, or both.