Skip to main content

Health condition

Pituitary disorders, too much, too little - and what presses on the eyes.

A pea-sized gland with an outsized reach. This hub explains hormone excess, hypopituitarism and mass effect, how they are tested for, and how they are treated under endocrine MDT care.

Jump to treatment
A radiographer guides a patient onto the bed of an advanced 3 Tesla MRI scanner in a London imaging suite

Why trust this guide

  • 01

    Editorial team

    Written by our editorial team from the UK sources listed on each page.

  • 02

    Sourced from guidance

    Checked against Society for Endocrinology guidance, Endocrine Society guidelines and NHS patient safety alerts, listed at the end.

  • 03

    Current for 2026

    Reflects modern UK practice including dopamine agonists first for prolactinoma, endoscopic surgery and steroid sick-day rules.

Key facts

Pituitary disorders at a glance.

The essentials, in plain English - what the gland does, the three patterns of disease, and who looks after you.

  • What it is

    A group of conditions of the pituitary - a pea-sized gland at the base of the brain that directs the thyroid, adrenals, ovaries, testes, growth and water balance.

  • Three patterns

    Too much of a hormone, too little of one or more hormones, or pressure on nearby structures such as the optic chiasm. Many people have more than one pattern.

  • Hormone excess

    Prolactinoma (prolactin), acromegaly (growth hormone) and Cushing disease (ACTH) are the three main functioning tumours.

  • Hormone deficiency

    Hypopituitarism can follow a tumour, surgery, radiotherapy, head injury or, rarely, postpartum haemorrhage (Sheehan syndrome).

  • Mass effect

    A larger tumour can cause headache and the classic loss of outer visual fields - bitemporal hemianopia - by pressing on the optic chiasm.

  • Specialist care

    Diagnosis and treatment are best led by an endocrinologist working with a pituitary neurosurgeon and ophthalmology in a dedicated MDT.

Why this guide matters

Slow signals, easily mistaken for something else.

Pituitary disease is often diagnosed years after the first symptom. Three ideas help you and your GP get there sooner.

  • Symptoms look ordinary

    Fatigue, weight change, low libido, headache and irregular periods have many common causes. It is the combination, and the persistence, that points to the pituitary.

  • Tests are specific

    A hormone panel, targeted dynamic tests and a dedicated pituitary MRI answer the question precisely. A routine brain scan can miss a small adenoma.

  • Two conditions are emergencies

    Pituitary apoplexy and adrenal crisis can be life-threatening within hours. Knowing the warning signs, and carrying a steroid card if you need one, saves lives.

Explore the pituitary family

How the diagnosis is made

From a hunch to a hormone-by-hormone answer.

The steps a UK GP and endocrinologist will normally follow, in order - so you know what to expect and why.

  1. 01

    Assessing

    History and medicines review

    Symptoms of excess, deficiency and mass effect are mapped. Pregnancy is excluded, and drugs that raise prolactin - such as some antipsychotics and antiemetics - are reviewed.

  2. 02

    Assessing

    Examination and visual screen

    Blood pressure, body habitus, skin and a bedside visual field check by confrontation. Any suspected field loss moves the pathway up the queue.

  3. 03

    Assessing

    Pituitary hormone panel

    Prolactin, IGF-1, a 9am cortisol, thyroid function with free T4, LH, FSH, testosterone or oestradiol, plus sodium and osmolality.

  4. 04

    Confirming

    Dynamic function tests

    Short synacthen test for cortisol reserve, oral glucose tolerance test for growth hormone suppression, dexamethasone suppression for Cushing, water deprivation or copeptin for diabetes insipidus.

  5. 05

    Confirming

    Dedicated pituitary MRI

    Thin-slice MRI with contrast shows the gland, any tumour, its size and its relationship to the optic chiasm and cavernous sinuses.

  6. 06

    Confirming

    Formal visual fields and OCT

    Perimetry, visual acuity and optical coherence tomography where MRI shows a lesion touching the chiasm, giving a baseline for later comparison.

  7. 07

    Planning

    Endocrine MDT decision

    Endocrinology, neurosurgery, neuroradiology, ophthalmology and oncology agree on medical therapy, surgery, radiotherapy or watchful monitoring.

Typical timeline: a first appointment to a full plan in a few weeks, faster if vision is affected.

Related tests: hormonal blood tests and MRI scanning.

Symptoms

What pituitary disease actually looks like.

Grouped by mechanism - excess, deficiency, pressure and water balance - and the one pattern that means emergency care.

  • Prolactin excess

    Milky breast discharge (galactorrhoea), missed or absent periods, low libido, erectile dysfunction and reduced fertility.

  • Growth hormone excess

    Enlarging hands, feet and jaw, changing ring or shoe size, coarsening features, sweating, snoring and joint pain.

  • Cortisol excess

    Central weight gain, rounded face, purple stretch marks, easy bruising, high blood pressure and raised blood sugar.

  • Hormone deficiency

    Persistent fatigue, feeling cold, dizziness on standing, low mood, low libido, loss of body hair and poor appetite.

  • Headache

    A persistent, often frontal or retro-orbital headache that does not follow the usual migraine or tension pattern.

  • Loss of outer vision

    Bumping into doorframes or missing objects at the sides - the bitemporal hemianopia of chiasmal compression.

  • Thirst and passing large volumes

    Intense thirst and pale, dilute urine passed frequently, day and night - the hallmark of diabetes insipidus.

  • Red flag - apoplexy

    Sudden severe headache with visual loss, double vision or collapse is an emergency. Call 999.

Treatment

How pituitary disorders are treated in the UK.

Treatment follows the diagnosis: tablets for prolactinoma, surgery for most others, then replacement of whatever hormones remain low. For tumour-specific detail see the pituitary tumours guide.

  • Cabergoline for prolactinoma

    A dopamine agonist that normalises prolactin and usually shrinks the tumour, restoring periods, fertility and libido. First-line for almost all prolactinomas.

  • Transsphenoidal surgery

    Endoscopic removal through the nose, with no external incision. First-line for Cushing disease and acromegaly where feasible, and for tumours threatening vision.

    Pituitary tumour removal

  • Somatostatin analogues

    Octreotide and lanreotide lower growth hormone and IGF-1 in acromegaly, before or after surgery, or when surgery is not possible.

  • Pegvisomant

    A growth hormone receptor blocker for acromegaly that persists on analogues. Dose is titrated to IGF-1 rather than to growth hormone itself.

  • Medical therapy for Cushing disease

    Metyrapone, osilodrostat or pasireotide can lower cortisol before surgery, after failed surgery or while radiotherapy takes effect.

  • Radiotherapy and radiosurgery

    Fractionated radiotherapy or single-session radiosurgery for residual or recurrent tumour. Effect builds over years and can cause later hormone loss.

    Stereotactic radiosurgery

  • Hormone replacement therapy

    Hydrocortisone, levothyroxine, sex steroids, growth hormone and desmopressin are replaced as needed. Cortisol is always started before thyroid hormone.

  • Steroid safety and lifelong review

    A steroid emergency card, sick-day rules and an injectable hydrocortisone kit, with annual endocrine review and repeat MRI and visual fields as advised.

What this guide is based on

The sources behind every claim on this page.

UK national guidance and specialist society standards, current at the time of last review.

Key references

Guidelines and standards we relied on.

A quiet reminder

This guide is for information, not medical advice.

Your GP or endocrinologist knows your history and results and can tell you which parts apply to you. If in doubt, get seen.

  • Society for Endocrinology. Endocrine Emergency Guidance: acute adrenal insufficiency and adrenal crisis.

  • Society for Endocrinology. Guidance for the management of pituitary apoplexy (Clinical Endocrinology).

  • Endocrine Society. Clinical practice guidelines on hyperprolactinaemia, acromegaly, Cushing’s syndrome and hormonal replacement in hypopituitarism.

  • NHS England. National Patient Safety Alert: Steroid Emergency Card for adults at risk of adrenal crisis.

  • NICE Clinical Knowledge Summaries. Hyperprolactinaemia and hypopituitarism.

Red flags

When pituitary disease is an emergency.

Most pituitary conditions are managed calmly over months. These are the situations that are not - call 999 or attend A&E, and tell staff about any pituitary diagnosis or steroid treatment.

  • Pituitary apoplexy

    Sudden severe headache with visual loss, double vision, drooping eyelid, vomiting or reduced consciousness - bleeding or infarction of a pituitary tumour. Call 999 or attend A&E at once.

  • Adrenal crisis

    Vomiting, severe weakness, low blood pressure, confusion or collapse in someone with cortisol deficiency. Needs immediate injected hydrocortisone and fluids.

  • Rapidly worsening vision

    New or fast-progressing field loss or blurring needs same-day assessment - the optic pathway can be permanently damaged if compression is not relieved.

  • Illness without steroid cover

    Fever, infection, injury or surgery in anyone taking hydrocortisone or prednisolone requires the dose to be increased. Missing this is the commonest trigger for crisis.

  • Unable to keep tablets down

    Vomiting or diarrhoea prevents absorption of steroid replacement. Use the emergency injection and go to hospital - do not wait to see if it settles.

  • Collapse after childbirth

    Severe postpartum haemorrhage followed by failure to breastfeed, exhaustion and low blood pressure can signal Sheehan syndrome - urgent hormone testing is needed.

  • Double vision or drooping eyelid

    Suggests spread of a tumour into the cavernous sinus or a bleed within it, affecting the nerves that move the eye. Needs urgent imaging.

  • Extreme thirst with confusion

    Uncontrolled diabetes insipidus can cause dangerous sodium and fluid shifts, especially after pituitary surgery or when desmopressin is missed.

  • Headache or vision change in pregnancy

    Pituitary tumours can enlarge during pregnancy. New headache or field loss needs urgent visual assessment and specialist review.

Living with it

A lifelong condition, well managed with the right safeguards.

Four habits that matter most day to day - steroid safety, regular review, planning ahead for family, and looking after wellbeing.

A quiet reminder

Replacement hormones are not optional extras.

Never stop hydrocortisone or levothyroxine without advice. Missed cortisol is the one gap that can become an emergency in a matter of hours.

  1. 01 Safety

    Carry the steroid emergency card

    Anyone on long-term hydrocortisone should carry the NHS steroid emergency card, wear a medical alert bracelet and keep an in-date injection kit. Learn the sick-day rules: double or triple the dose for fever, and inject if vomiting.

  2. 02 Follow-up

    Expect lifelong monitoring

    Even after successful treatment, tumours can recur and hormone levels can drift. Regular blood tests, periodic MRI and visual fields keep any change small and treatable.

  3. 03 Family

    Plan fertility and pregnancy

    Prolactinoma and hypopituitarism often reduce fertility, but treatment frequently restores it. Talk to your endocrine team before conceiving so doses and imaging can be planned.

  4. 04 Wellbeing

    Look after energy, mood and support

    Fatigue and low mood are common even when hormones look well replaced. Ask for dose review, sleep and activity support, and consider peer groups such as The Pituitary Foundation.

Frequently asked

Everything we get asked about pituitary disorders.

Quick answers on what the pituitary does, the tests, surgery and steroid safety.

  • What does the pituitary gland do?

    It sits beneath the brain and releases hormones that control the thyroid, adrenal glands, ovaries and testes, growth, breast milk production and water balance through the kidneys. Because it directs so many systems, a fault in one small gland can have wide effects.

  • What are the main types of pituitary disorder?

    They fall into three groups. Hormone excess includes prolactinoma, acromegaly and Cushing disease. Hormone deficiency is called hypopituitarism and includes Sheehan syndrome. Mass effect covers headache and visual field loss from a larger tumour. Diabetes insipidus, a water-balance problem, can occur with any of these.

  • Are pituitary tumours cancer?

    Almost never. The great majority are benign adenomas that grow slowly and do not spread. They can still cause serious problems through excess hormones or pressure on the optic nerves, so they need proper assessment and often lifelong follow-up.

  • Which tests will I need?

    Usually a pituitary blood panel and a dedicated MRI of the pituitary. Depending on the picture, dynamic tests such as a short synacthen test, a glucose tolerance test for growth hormone, dexamethasone suppression or a water deprivation test may be added, along with formal visual field testing.

  • Will I need surgery?

    Not always. Prolactinomas are treated with cabergoline first. Surgery is the first choice for most Cushing disease and acromegaly and for any tumour threatening vision. Some small, non-functioning tumours are simply monitored with scans. The endocrine MDT weighs these options with you.

  • Why do I need a steroid emergency card?

    If your body cannot make enough cortisol, illness, injury or surgery can trigger an adrenal crisis - a life-threatening collapse. The card tells paramedics and hospital staff to give injected hydrocortisone straight away, without waiting for tests. Carry it at all times.

Related content

Keep reading.