The endocrine system produces hormones---chemicals produced in one part of the body to regulate another part of the body. Hormones regulate nearly all cellular functions. The adrenal glands, a pair of glands located above each kidney, work within the endocrine system to affect physical characteristics, growth and development. Adrenal insufficiency describes the condition that occurs when the adrenal glands fail to produce enough hormones.
Adrenal Gland Function
The adrenal glands contain two separate sections that perform separate functions. The outer layer of the gland, known as the adrenal cortex, produces steroid hormones including the mineralocorticoid aldosterone, the glucocorticoid cortisol and some sex steroids. The inner layer, known as the adrenal medulla, produces hormones classified as catecholamines. Approximately 80 percent of the hormone produced by the adrenal medulla is epinephrine and 20 percent is norepinephrine, according to Colorado State University. These hormones function within the nervous system inducing the heart to beat harder and faster and blood vessels to constrict.
Primary Adrenal Insufficiency
Successfully treating adrenal insufficiency depends upon the cause and therefore the type of the disease. Primary adrenal insufficiency occurs when the adrenal gland sustains damage and fails to produce enough hormones. This condition, known as Addison's disease, affects four of every 100,000 people in the United States, according to the National Endocrine and Metabolic Diseases Information Service.
Secondary Adrenal Insufficiency
The pituitary gland, the master endocrine gland found near the base of the brain, secretes many different hormones including adrenocorticotropic hormone which stimulates the adrenal gland to produce the hormones. When the pituitary fails to produce enough adrenocorticotropic hormone, due to a pituitary malfunction, the adrenal glands cannot produce enough hormones. Doctors classify this type of adrenal insufficiency as secondary adrenal insufficiency.
Symptoms
Because the hormones produced by the adrenal glands help to regulate the break down and use of proteins, carbohydrates and fats, as well as regulating blood pressure and volume, the symptoms of adrenal insufficiency affect many bodily functions. Common symptoms include chronic fatigue, weak muscles, loss of appetite and weight loss. Adrenal insufficiency also affects the heart and blood vessels causing low blood pressure that leads to dizziness and fainting. Other symptoms include nausea, vomiting, diarrhea, irritability, depression, headache and sweating.
Hormone Treatment
Although some patients may try to treat individual symptoms, once they receive the diagnosis of adrenal insufficiency, the most effective treatment involves hormone replacement therapy, according to MayoClinic.com. Hormone replacement therapy uses a mixture of oral corticosteroids, such as hydrocortisone to replace cortisol levels and mineralocorticoid such as fludrocortisones to replace aldosterone levels. Patients suffering from secondary adrenal insufficiency often maintain normal aldosterone levels; therefore they only need to take the corticosteroid. Women experiencing symptoms of lowered levels of sex hormones can benefit from androgen replacement therapy, such as dehydroepiandrosterone.
