Hormones are the chemical messengers produced by the endocrine (hormone producing) glands in our body. They play a very significant role in regulating body functions. Pituitary gland is the main endocrine gland and it controls the functions of other endocrine glands of our body.
Pituitary gland (also known as hypophysis), is a small pea-sized gland situated below the hypothalamus. It is called the ‘Master Gland’ since it produces eight hormones which act on other endocrine glands such as ovaries, testes, adrenocortical region, thyroid and mammary gland to stimulate their hormone production. This allows them to function normally. Pituitary gland has two distinct parts, the anterior lobe and the posterior lobe. Each of this lobe produces their hormones with specific function.
What Happens if Pituitary Gland is Removed?
Pituitary gland is an important gland since it maintains body’s overall well-being. It faces problem in the form of pituitary gland tumors, cysts, infection and inflammation. Pituitary tumors cause over or under production of hormones. Tumors also cause vision problems like loss of vision or double vision. To overcome this problem, the tumor is surgically removed or treated with radiation therapy. During surgical removal of pituitary adenomas, pituitary gland may be completely removed from the body. This leads to loss of all its hormone production and causes a condition called hypopituitarism. This in turn severely affects the normal function of other endocrine glands which the pituitary gland controls.
The outcome of the removal of pituitary gland is hormonal imbalance which can lead to the following specific symptoms:
- Loss of growth hormone leads to dwarfism in children and it alters body composition in adults.
- Absence of Follicle Stimulating Hormone and Luteinizing Hormone leads to irregularities in menstruation and causes infertility.
- Prolactin deficiency causes failure in production of breast milk from mammary gland.
- If pituitary gland is removed, there will be loss of oxytocin which causes problems during childbirth.
- Removal of pituitary gland causes Antidiuretic Hormone deficiency which leads to symptoms of polyuria and polydipsia.
Other non-specific symptoms which a person can experience if the pituitary gland is removed include weakness, nausea, loss of weight, tiredness, feeling cold, loss of erections and loss of sex drive in men. Thus, metabolism, fertility, water absorption and reproduction are highly disturbed in an individual.
After removal of the pituitary gland, there is severe deficiency of its important hormones. This hormonal imbalance is life threatening. Pituitary hormones are necessary for survival; hence the patient is treated with the Hormone Replacement Therapy (HRT). The goal of HRT is to deliver synthetic hormones to replace the function of important glands controlled by pituitary gland. It involves administration of synthetically made thyroid, growth, testosterone and adrenal hormones. Only prolactin is not given; since unlike other hormones, lack of prolactin does not cause serious effects. Different hormones are administered by different ways such as oral tablets, injectable and nasal sprays such as:
- Synthetic growth hormone is to be injected daily before going to bed. This helps to overcome the growth hormone deficiency.
- Adrenocorticotropic hormone is replaced by tablets of hydrocortisone or prednisone which is to be taken two or three times daily.
- Thyroxine in tablet form overcomes deficiency of TSH and is to be taken once a day.
- Estrogen/progesterone hormones are given to replace female sex hormones.
- Testosterone is given to replace male sex hormones. It can be taken in different forms such as injections, transdermal patches and gels.
- Demopressin tablets or nasal sprays help in overcoming the deficiency of antidiuretic hormone.
Hormone therapy has to be taken under supervision of a medical doctor. Further, blood levels of hormones need to be monitored for adjustments of doses. Every patient requires different dose of hormone during therapy. The patients should not stop any medications without consulting a doctor. If hormone replacement therapy is not followed properly, it may lead to serious complications and hence, it has to be followed for the entire life.
After removal of pituitary gland, hormonal replacement therapy is available to overcome hypopituitarism. Although a lifesaving therapy, hormone replacement therapy is complex, expensive and a cumbersome life-long process. Hence, during surgical removal of pituitary tumours, efforts should be made to preserve the pituitary gland at all possible cases.