A pheochromocytoma (fee-o-kroe-moe-sy-TOE-muh) is a rare, usually noncancerous (benign) tumor that develops in an adrenal gland. You have two adrenal glands —one located at the top of each kidney. Usually, a pheochromocytoma develops in only one adrenal gland. But tumors can develop in both.

If you have a pheochromocytoma, the tumor releases hormones that may cause high blood pressure, headache, sweating and symptoms of a panic attack. If a pheochromocytoma isn't treated, severe or life-threatening damage to other body systems can result.

Most pheochromocytomas are discovered in people between the ages of 20 and 50. But the tumor can develop at any age. Surgery to remove a pheochromocytoma usually returns blood pressure to normal.


Signs and symptoms of pheochromocytomas often include:

  • High blood pressure
  • Headache
  • Heavy sweating
  • Rapid heartbeat
  • Tremors
  • Paleness in the face
  • Shortness of breath
  • Panic attack-type symptoms

Less common signs or symptoms may include:

  • Anxiety or sense of doom
  • Constipation
  • Weight loss

Symptomatic spells

The symptoms listed above may be constant, or they may occur, or get stronger, occasionally. Certain activities or conditions can make symptoms worse, such as:

  • Physical exertion
  • Anxiety or stress
  • Changes in body position
  • Labor and delivery
  • Surgery and anesthesia

Foods high in tyramine, a substance that affects blood pressure, also can make symptoms worse. Tyramine is common in foods that are fermented, aged, pickled, cured, overripe or spoiled. These foods include:

  • Some cheeses
  • Some beers and wines
  • Chocolate
  • Dried or smoked meats

Certain medications that can make symptoms worse include:

  • Monoamine oxidase inhibitors (MAOIs), such as phenelzine (Nardil), tranylcypromine (Parnate) and isocarboxazid (Marplan)
  • Stimulants, such as amphetamines or cocaine

When to see a doctor

Although high blood pressure is a primary sign of a pheochromocytoma, most people who have high blood pressure don't have an adrenal tumor. Talk to your doctor if any of the following factors are applicable to you:

  • Difficulty controlling high blood pressure with current treatment
  • Episodic worsening of high blood pressure
  • A family history of pheochromocytoma
  • A family history of a related genetic disorder: multiple endocrine neoplasia, type 2 (MEN 2); von Hippel-Lindau disease; familial paraganglioma or neurofibromatosis 1 (NF1)


Researchers don't know exactly what causes a pheochromocytoma. The tumor develops in specialized cells, called chromaffin cells, located in the center of an adrenal gland. These cells release certain hormones, primarily adrenaline (epinephrine) and noradrenaline (norepinephrine), that help control many body functions, such as heart rate, blood pressure and blood sugar.

The role of hormones

Adrenaline and noradrenaline trigger your body's fight-or-flight response to a perceived threat. The hormones cause your blood pressure to increase and your heart to beat faster. They prepare other body systems that enable you to react quickly. A pheochromocytoma causes more of these hormones to be released and causes them to be released when you're not in a threatening situation.

Related tumors

While most of the chromaffin cells are located in the adrenal glands, small clusters of these cells are also in the heart, head, neck, bladder, back wall of the abdomen and along the spine. Chromaffin cell tumors, called paragangliomas, may result in the same effects on the body.

Risk factors

People who have certain rare inherited disorders have an increased risk of pheochromocytoma or paraganglioma. Tumors associated with these disorders are more likely to be cancerous. These genetic conditions include:

  • Multiple endocrine neoplasia, type 2 (MEN 2) is a disorder that results in tumors in more than one part of the body's hormone-producing (endocrine) system. Other tumors associated with this condition can appear on the thyroid, parathyroid, lips, tongue and gastrointestinal tract.
  • Von Hippel-Lindau disease can result in tumors at multiple sites, including the central nervous system, endocrine system, pancreas and kidneys.
  • Neurofibromatosis 1 (NF1) results in multiple tumors in the skin (neurofibromas), pigmented skin spots and tumors of the optic nerve.
  • Hereditary paraganglioma syndromes are inherited disorders that result in either pheochromocytomas or paragangliomas.


High blood pressure can damage multiple organs, particularly tissues of the cardiovascular system, brain and kidneys. This damage can cause a number of critical conditions, including:

  • Heart disease
  • Stroke
  • Kidney failure
  • Problems with the nerves of the eye

Cancerous tumors

Rarely, a pheochromocytoma is cancerous (malignant), and the cancerous cells spread to other parts of the body. Cancerous cells from a pheochromocytoma or paraganglioma most often travel to the lymph system, bones, liver or lungs.

March 03, 2020
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