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What is the Pituitary gland and what does it do?Your pituitary is an important gland and is often referred to as the 'master gland', because it controls several other hormone glands including the thyroid and adrenals (which produce hormones essential for life) and the ovaries and testicles (for sex and reproduction). The pituitary gland is about the size of a pea and is situated in a bony hollow beneath the base of your brain and just behind the bridge of your nose. The pituitary in turn is controlled by a part of the brain called the Hypothalamus, which is situated immediately above the pituitary gland. When your pituitary is functioning normally it produces a number of hormones: ![[Female body showing major glands]](/images/stories/hyp-bodyf.gif) ![[Male body showing major glands]](/images/stories/hyp-bodym.gif)
This may also be referred to as ACTH, or corticotrophin. This hormone stimulates your Adrenal glands (situated just above your kidneys) to produce a hormone called Cortisol. The adrenal hormones are essential for life and help us to cope with stress. This hormone is secreted from the back part of your pituitary, and it is sent from the pituitary to the kidneys to limit the volume of urine produced. It is also known as Vasopressin. These hormones control sex and reproduction. The two Sex hormones made by the pituitary are Luteinising hormone (often referred to as LH) and follicle stimulating hormone (FSH). In women, these hormones are sent through the bloodstream from the pituitary to the ovaries, where they control ovulation. They are thus essential for a normal menstrual cycle and for fertility. In men, these hormones are sent to the testes, where LH stimulates the production of the male hormone Testosterone, and FSH is important in sperm production. In children, LH and FSH control sexual development during puberty. This is often abbreviated to GH. In children this hormone is essential for a normal rate of growth. In adult life growth hormone is also important for a number of functions, including normal energy levels. This hormone stimulates the breasts to make milk. It is present all the time in both men and women, but is produced in large amounts during pregnancy and breastfeeding. You may also hear this referred to as TSH, or sometimes as Thyrotrophin. As its name suggests, this hormone stimulates your Thyroid Gland (located near your windpipe) to produce its own hormone, which is called Thyroxine. The thyroid gland controls many body functions, including heart rate and metabolism. What can go wrong with my pituitary gland?The most common problem with the pituitary occurs when a Benign tumour (also called an adenoma) develops. The term 'benign' is used by doctors to describe a swelling which is not cancerous. Some pituitary tumours can exist for years without producing symptoms and, indeed, some never produce symptoms. Most pituitary tumours occur in people with no family history of pituitary problems, and the condition is not usually passed on from generation to generation. Only very occasionally (for example in a condition known as multiple endocrine neoplasia or MEN-1), is the tendency to develop pituitary tumours inherited. A Pituitary tumour may cause you problems because it gives you headaches or because it presses on the optic nerve, which could cause you to have trouble with your eyesight. These are sometimes the first symptoms and many patients are initially referred to a specialist by their optician. By far the most common type of tumour (about half of all cases) is the 'non-functioning' tumour. This is a tumour that does not produce any hormones itself. It can cause headaches and visual problems, as detailed later in this leaflet, or it can press on the pituitary gland, causing it to stop producing the required amount of one or more of the pituitary hormones. This effect can also be produced by the treatment you are given for a tumour, such as surgery or Radiotherapy. Alternatively, your pituitary tumour may begin to generate too much of one or more hormones. Craniopharyngioma is a rare and congenital (from birth) tumour that exerts pressure on the hypothalamus and often on the pituitary gland. Fast-growing ones affect children and slower ones adults. They cause headaches and visual problems. Pressure on the hypothalamus affects temperature regulation, hunger, thirst (Diabetes Insipidus), sleep patterns, emotional behaviour and memory. Being the 'communications centre', the pressured hypothalamus often sends signals to the pituitary gland that affect the production of growth hormone and the onset of puberty. For further details, please see our GP Factfile, sheet 7 and the Child Growth Foundation's leaflet 'Craniopharyngioma: A Guide for Parents and Patients'. Underproduction of pituitary hormonesUnderproduction of one or more hormones by the pituitary gland is known as hypopituitarism. It is generally treated by replacing the hormones normally produced by the glands that your pituitary controls. Brief details are given below, but for further information, please see our leaflet entitled 'Hypopituitarism and Replacement Therapy'. Adrenocorticotrophic hormone (ACTH)Lack of ACTH is characterised by fatigue, light-headedness (often on standing - postural hypotension) and loss of physical well-being and vigour. Lack of ACTH is usually treated with Hydrocortisone, which is a synthetic version of the hormone cortisol. This is in tablet form and is usually taken two or three times daily. Anti-diuretic hormone (ADH), also called vasopressin![[The symptoms of DI include thirst and a constant need to go to the toilet.]](/images/stories/di-loo.gif) Lack of ADH can be caused by injury to, or inflammation of, the pituitary gland or the hypothalamus. It can sometimes occur after pituitary surgery, but this is usually only temporary. If your pituitary does not send enough ADH to your kidneys, they will not be able to regulate the flow of urine. This condition is called diabetes insipidus (DI), but is nothing to do with diabetes mellitus (sugar diabetes)! Diabetes insipidus causes a continual thirst and need to pass water, even during the night. You may find yourself drinking four or five gallons of water a day. DI is treated using a substance called Desmopressin, which affects your kidneys in the same way your own ADH should do. Desmopressin is usually prescribed as a nasal spray, but it is also available in a tablet form. For further details, please see leaflet entitled 'Diabetes Insipidus'.
GonadotrophinsIn women, lack of the gonadotrophins causes problems with the menstrual cycle, fertility and sex drive. In men, there may be problems with fertility, impotence and sex drive. You may also feel generally tired. Women are usually treated with hormone replacement tablets. For men, treatment may involve injections once or twice a month. Children who lack gonadotrophins have delayed or absent pubertal development and may require treatment with sex hormones to induce the physical changes of puberty. For further details, please see our leaflets entitled 'Prolactinoma' and 'Hypogonadism and Infertility: A Guide for Men'. Growth hormoneIn children, lack of growth hormone will mean that the child is smaller than his/her peers, and may also be younger-looking and overweight. This is treated by use of synthetic growth hormone, which is normally injected daily. For adults, the situation is less clear, but a lack of growth hormone can affect general energy levels and wellbeing, and can lead to an increased risk of Osteoporosis and probably also heart disease. Studies show that, for some patients, GH replacement should continue in adult life to improve quality of life. For further details, please see our leaflet entitled 'Adult Growth Hormone Replacement'. ProlactinThere are usually few symptoms or problems caused by a lack of prolactin, although women with low prolactin may find they are unable to breastfeed. Thyroid stimulating hormoneLack of this hormone will cause your thyroid to be underactive (Hypothyroidism). Fatigue and weight gain are very common. You may feel tired and generally unwell. Treatment is with hormone tablets (thyroxine) taken daily. Overproduction of pituitary hormonesAdrenocorticotrophic hormoneOverproduction of ACTH can cause your adrenal glands to produce too much cortisol, leading to an illness called Cushing's disease. This is characterised by an increase in weight, redness and roundness of the face, mood swings, and feelings of tiredness and depression. Cushing's is more common in women, who may find their periods become irregular or even stop altogether, as well as finding an increase in body hair. Men with Cushing's can suffer from loss of fertility and sex drive. The condition is usually treated by means of an operation to remove the tumour, which is causing the problem. For further details, please see our leaflet entitled 'Cushing's'. Growth hormoneDuring childhood, overproduction of growth hormone can cause the child to grow faster than normal. If untreated, the resulting adult could be extremely tall. This is called Gigantism. Overproduction of growth hormone in adults can lead to a condition called Acromegaly. Symptoms include headaches, visual problems, sweating and an increase in shoe or glove size, as well as some changes in facial features, such as increased prominence of the jaw. These changes can be very gradual and may therefore go unnoticed by close family members and friends. The condition is usually treated by one, or more, of surgery, radiotherapy and drug treatment. For further details, please see our leaflet entitled 'Acromegaly'. ProlactinOverproduction of prolactin is called Hyperprolactinaemia and can be due to one of several causes. It can be caused by certain medications, especially certain anti-sickness tablets or tranquillisers. If your thyroid gland is underactive this could be the culprit. Thirdly, it could be due to a benign tumour, which is itself producing prolactin. This type of tumour is called a Prolactinoma. Prolactinomas are usually less than one centimetre in diameter although they can occasionally be larger. They tend to interfere with production of sex hormones. Prolactinomas in women are usually small and symptoms are likely to be irregular or absent periods, problems with fertility, and production of breast milk when not pregnant or breastfeeding. Men often have larger prolactinomas and symptoms include loss of sex drive, impotence and production of breast milk. In both sexes, treatment with tablets is usually very effective, restoring sex drive and fertility, often very quickly. For further details, please see our leaflet entitled 'Prolactinoma'. Visual problemsBecause a pituitary tumour can sometimes press on the optic nerve, which passes over it, you may have problems with your vision. You may find that your field of vision gets smaller - rather as if you were wearing blinkers. This can happen to one eye or to both, and may be accompanied by headaches. The treatment you are given for your tumour (usually drug treatment for prolactinoma and surgery for other types) has a good chance of helping this. Your vision may improve and could even return to normal. You may be seen by an eye specialist (ophthalmologist) as well as by your Endocrinologist if you have visual problems. InfertilityInfertility is a very common problem that affects up to one in six couples that are trying to conceive. In addition, something like one in ten couples with normal fertility will take at least a year to conceive. ![[Drug treatments for prolactinomas]](/images/stories/prol-drugs.gif) Hormone problems cause around a quarter of all infertility and the pituitary gland is very important in this connection, as it provides the gonadotrophins (LH and FSH), which are necessary for the ovaries or testicles to function properly. The most common cause of pituitary-related infertility is a raised level of prolactin, usually due to a pituitary tumour called a prolactinoma. This can be treated fairly easily with medicines, prescribed by a specialist, which reduce prolactin production by the pituitary. There are three of these currently in use: cabergoline (brand name Dostinex), Bromocriptine (brand name Parlodel) and quinagolide (brand name Norprolac). For further details, please see our leaflets, entitled 'Prolactinoma' and 'Hypogonadism and Infertility: A Guide for Men'.
Many other pituitary conditions can cause your levels of sex hormones to be too low. The treatment you are given for your particular condition may restore your fertility. If not, you will usually be treated with gonadotrophins, either by injections or by use of a small pump, which is worn with a belt. These methods are only needed until you are pregnant. For further details, see references to gonadotrophins elsewhere in this leaflet and also our leaflet entitled 'Hypopituitarism and Replacement Therapy'. Coping with the stress of a pituitary tumourIn addition to physical issues, many people find pituitary illness emotionally traumatic. Particularly if you were unwell for some time before a correct diagnosis was made, there may be stress caused either by specific physical aspects (e.g. loss of libido, overproduction of cortisol) or by factors such as change to body image, exhaustion, anxiety and so on. In addition, both the fear of anticipated surgery so close to the brain and the fact that, for some people recovery can take quite a while, can be stressful, particularly if it follows a long period of ill health leading up to the diagnosis. All these issues can be just as difficult for family and close friends as for the patients themselves. Your GP will be able to arrange counselling if this is required (see GP Factfile sheet 12). You may also find it useful to make contact with The Pituitary Foundation's support team in Bristol (telephone 0845 450 0375) and/or with your nearest local support group, where you will find many people keen to help and support you. Treatment of pituitary tumoursTreatment can be by one or more of surgery, radiotherapy and drugs. This depends on which condition is involved. Pituitary surgeryMany pituitary problems are caused by a benign tumour. An operation is often the best course of action, although it is not usually necessary in the case of a prolactinoma. We reassure you that modern pituitary surgery, by a specialist surgeon, is safe and a relatively small procedure. Most tumours are removed by a procedure called Transsphenoidal surgery. This involves the surgeon making a small incision through your nose or under the upper lip. By using this route, your surgeon can see your pituitary without disturbing the main part of your head. The operation normally involves about five days in hospital. You will be on a drip for a day or two and may also be given antibiotics to prevent any infection in your nose. Most people are up and about and eating normally the next day. Recovery times vary. Depending on the job and circumstances, you should plan for four to six weeks, maybe longer, away from work. You will need to avoid blowing your nose for three weeks and your front teeth may feel numb for a while. If you wear false teeth, you may find they do not fit very well until the swelling goes down, but this should only be for a few days. For a few days after the operation, some patients feel very thirsty and need to pass urine more than normal. Occasionally this condition, called diabetes insipidus, is permanent. It can be treated by the use of a drug called desmopressin. For further details please see our leaflet entitled 'Diabetes Insipidus'. Sometimes the surgical opening needs patching with tissue taken from the thigh. This would leave a small scar on your leg. Few patients have any unpleasant after-effects from this kind of surgery, but your surgeon will tell you if there are any symptoms you should look out for. Depending on the reason for your pituitary surgery, you may be given follow-up treatment using radiotherapy and/or drug treatment. RadiotherapyRadiotherapy (treatment with X-rays) is sometimes used as a follow-up to surgery, or it can be recommended instead of surgery. The radiotherapy dose is much smaller than that for cancer patients. Radiotherapy is planned and carried out with extreme care. It is usually administered through three parts of the head - one on top of your scalp and one near each ear. About a week will be spent planning exactly where the X-rays will go, and an individual head mask may be made for you. The treatment itself will be carried out daily on weekdays and will last several weeks. The effects are gradual and will take some time to be complete. Also, radiotherapy can result in a gradual decline in the function of any remaining normal pituitary tissue, resulting in hypopituitarism. For these reasons long-term follow-up is needed. Medical therapyMany pituitary conditions require treatment with drugs, either on their own or in addition to surgery and/or radiotherapy. These drugs may be used to reduce the levels of a hormone, which your pituitary is overproducing, or to replace a hormone, which your pituitary is underproducing. Full details are given in the relevant sections of this leaflet and in our other leaflets. Follow-up treatmentMost people with a pituitary tumour will be given regular check-ups at a specialist clinic for the rest of their life. This enables the specialist to monitor your condition and pick up any changes as soon as possible. In most patients, the condition remains stable after the original treatment. Sometimes, particularly after radiotherapy, the pituitary may not function adequately and replacement therapy then becomes necessary. For further details, please see our leaflet entitled 'Hypopituitarism and Replacement Therapy'). Regrowth of a pituitary tumour can occasionally happen if it was not possible to remove all of the tumour during surgery. The chance of this happening is lower if you had radiotherapy after your operation. If this does happen, you may need another operation, or radiotherapy if you did not have this before. What having a pituitary tumour has meant to meOne Patient's story "You will need to see your GP without delay". These were the words that greeted me after I had had eye tests at my local optician for blurring of vision in my right eye. Little did I realise that this was the beginning of a fortnight of X-rays, consultations, scans and blood tests as well as seemingly unrelated questions about my general health and well-being. The result of all of this was that I was diagnosed as having a pituitary tumour which, thankfully, was benign. However, due to its enlargement it was now obstructing my optic nerves, resulting in my blurred vision. Without intervention the condition would become steadily worse - I needed an operation. I was referred to a hospital where I was confined for nearly a week for yet more tests and scans, and a date was set for the operation. I admit to being scared both about the operation and for the future, despite the support I received from my family and friends and the knowledge that I would be in very experienced hands in the hospital. The day prior to the operation saw me settled in to a small ward for preparation. The night time was sleepless as I worried about the next few hours. This was a very lonely time for me. The operation took over two hours to perform, although I don't remember much of the following twelve hours. The surgery had been carried out through my top lip and up into the cavity at the back of my nose, resulting in no scars and I didn't have to have my head shaved as I originally thought I would. Apart from two drain tubes in my nose and a bandage across my face, the experience was not too uncomfortable. During the next few days I was constantly monitored for fluid balance and, as a result, was treated for the symptoms of diabetes insipidus, which manifested itself by extreme thirst causing me to consume vast quantities of fluid and subsequently spending a lot of time in the WC. Nine days after the operation I left the hospital feeling a little 'empty-headed', but once home I soon began to recuperate and subsequently returned to work three to four weeks later with my sight much improved in my right eye and completely cleared in my left, which had begun to deteriorate just prior to my operation. The following months saw me return to the hospital for tests to establish the effects that both the tumour and the operation had had on the other glands in my system. I now need replacement with steroid, thyroxine and DDAVP (for the DI), all of which are taken as a cocktail of tablets in the morning. It has become so habitual that I have to think twice whether I have eaten my Cornflakes! I still visit the hospital periodically to discuss my condition. I feel very well these days, although I still remember what a nurse said to me when I was in hospital "You will never be rid of us now," she said. I for one am glad that they are always there for me.
General information on lifestyle issues and useful addresses are also available on this web site. The aim of this page is to provide general information about the Pituitary Gland. It is written in general terms, therefore, not all of it will apply to you. Hopefully you will find it helps you to understand the Pituitary Gland better and gives you a basis for discussion with your GP or endocrinologist. We would like to emphasise that all patients are different and you should always seek advice from your specialist or GP.
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