Health condition
Cushing's disease vs syndrome
Cushing's syndrome means cortisol excess from any cause; Cushing's disease is the specific form driven by an ACTH-producing pituitary adenoma - the distinction decides treatment.
Why trust this guide
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Editorial team
Written by our editorial team from the UK sources listed on each page.
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Sourced from guidance
Checked against current NHS and UK specialist society guidance at the time of review.
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Current for 2026
Reviewed on 2026-09-27 with the next review scheduled for 2027-09-27.
Key facts
The essentials at a glance.
The symptoms to recognise, when to seek help, which specialist to see, and what treatment usually involves.
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Cushing's syndrome: cortisol excess from any source, including steroid medication, adrenal tumours and pituitary disease
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Cushing's disease: a pituitary adenoma making ACTH, the commonest non-medication cause
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First-line tests: overnight dexamethasone suppression test, late-night salivary cortisol, or 24-hour urinary free cortisol
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ACTH levels then separate pituitary and adrenal causes; pituitary MRI and sometimes petrosal sinus sampling follow
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Specialist: a consultant endocrinologist, with pituitary MDT input for Cushing's disease
Understanding the condition
What it is and what happens next.
What causes it, how it is diagnosed, and the treatment routes available in the UK.
What it is and how it feels
Cortisol excess produces weight gain around the trunk and face, easy bruising, purple stretch marks, muscle weakness climbing stairs, thin skin, mood change, high blood pressure and diabetes. By far the commonest cause is steroid medication. Among internal causes, a small ACTH-secreting pituitary adenoma (Cushing's disease) leads, followed by cortisol-producing adrenal tumours and, rarely, ACTH made elsewhere in the body.
Diagnosis and treatment routes
Confirming cortisol excess comes first - dexamethasone suppression testing, late-night salivary cortisol or urinary free cortisol, usually more than once - and only then is the source hunted with ACTH levels, imaging and, where needed, inferior petrosal sinus sampling. Treatment is directed at the cause, most often pituitary surgery. Diagnosis is notoriously slow; NHS endocrinology waits of 20-45+ weeks are common, while a private endocrinologist can typically begin the workup within about two weeks.
Seeing a specialist
Who to see, and how quickly you can be seen.
The specialist for this condition is usually a consultant endocrinologist. Your GP can refer you on the NHS, or you can arrange a private consultation directly.
A quiet reminder
This guide is for information, not medical advice.
Your GP knows your history and can tell you which parts apply to you. If in doubt, see them - and seek urgent care for any of the emergency symptoms described above.
Frequently asked
Common questions about Cushing's disease vs syndrome.
Quick, plain-English answers to what people ask us most.
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What's the difference between Cushing's disease and Cushing's syndrome?
Cushing's syndrome means cortisol excess from any cause, while Cushing's disease is the specific form driven by an ACTH-producing pituitary tumour - the distinction decides which gland is treated and which specific treatment approach is used.
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What causes Cushing's syndrome in general?
The most common cause overall is long-term steroid medication use, while endogenous (naturally produced) excess cortisol can come from a pituitary tumour (Cushing's disease), an adrenal tumour, or, rarely, a tumour elsewhere producing ACTH.
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What are the symptoms shared by both conditions?
Both cause the same general features of excess cortisol: weight gain (particularly around the face and trunk), thin, easily bruised skin, purple stretch marks, muscle weakness, and high blood pressure.
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Is Cushing's disease more dangerous than Cushing's syndrome generally?
Both share the same risks of excess cortisol (high blood pressure, diabetes, osteoporosis), but Cushing's disease specifically also carries risks related to the pituitary tumour itself, such as effects on other pituitary hormones or, rarely, vision if the tumour is large.
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How do doctors distinguish Cushing's disease from other causes of Cushing's syndrome?
This involves specific blood tests (such as ACTH levels) and imaging of the pituitary and adrenal glands, sometimes combined with more specialised testing, to pinpoint exactly where the excess cortisol production is coming from.
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How is Cushing's disease treated differently from other causes?
Cushing's disease is typically treated with transsphenoidal surgery to remove the pituitary tumour, whereas an adrenal cause is treated with adrenal surgery, and steroid-induced Cushing's syndrome is managed by reducing the steroid dose where possible.
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Can both conditions be cured?
Surgical removal of a pituitary or adrenal tumour can be curative in many cases, and steroid-induced Cushing's syndrome typically resolves once steroid treatment is safely reduced or stopped, though this needs careful medical supervision.
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How long does treatment take to work?
Recovery timeframes vary by cause and treatment - surgical cases often show improvement over weeks to months, while cortisol levels and symptoms take time to normalise even after the underlying cause is successfully addressed.
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Why does the distinction between Cushing's disease and syndrome matter?
Getting the diagnosis right determines exactly which treatment (pituitary surgery, adrenal surgery, or steroid dose reduction) will actually address the underlying problem, so accurate testing to distinguish the cause is a critical step before treatment.
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When should I see a specialist to clarify which type I have?
See an endocrinologist for thorough testing if you have features of Cushing's syndrome, so the exact cause can be identified and the right treatment chosen. A private endocrinology consultation is often available within about two weeks.