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Addison’s Disease / Adrenal Insufficiency UK primary care pathway · RCGP SCA preparation · adrenal crisis & sick-day rules
Progress 0 / 9
The full reasoning pathway — adrenal crisis is the emergency (treat before confirming); for chronic presentation confirm with 9am cortisol / short Synacthen, split primary vs secondary, replace steroids, embed sick-day rules, and safety-net.StartDecisionInvestigateActionReferStop / Admit
PresentationSuspected adrenal insufficiency
Fatigue, weight loss, postural dizziness, pigmentation; biochemistry of low Na⁺ + high K⁺ ± hypoglycaemia.
Step 1 · Safety — adrenal crisis (NG243)Adrenal crisis?
Critically unwell with hypotension/postural drop, shock/collapse, vomiting, profound weakness, hyponatraemia, hypoglycaemia, hyperpigmentation. Or milder symptoms in someone with known/high-risk adrenal insufficiency (the commoner primary-care presentation) — often precipitated by illness or steroid withdrawal.
YES
Stop · AdmitHydrocortisone 100mg IM/IV + fluids → 999
Give hydrocortisone 100mg IM or IV immediately (anyone — patient/relative/carer — can give it IM); do not wait for results. IV fluids (in hospital, 1L 0.9% saline over 30 min). Rapid transport to hospital, ideally within 30 min.
NO
Investigate9am cortisol + short Synacthen
U&E, glucose, ACTH; adrenal autoantibodies. Low 9am cortisol → confirmatory test.
Step 3 · primary or secondary?
Primary (Addison's)
High ACTH
Autoimmune (commonest), TB; pigmentation, high K⁺. Needs gluco- + mineralocorticoid.
Secondary
Low ACTH
Steroid withdrawal (commonest), pituitary disease. No hyperpigmentation; K⁺ normal.
ReferEndocrinology
Endocrinology for all confirmed cases — replacement, sick-day rules, steroid emergency card, and IM hydrocortisone for home.
Step 8 · sick-day rules & self-management
Step 8 · Sick-day rules & self-managementPrevention beats treatment
Double oral hydrocortisone during fever/illness; IM hydrocortisone for vomiting/D&V or before surgery/procedures. Ensure the patient (and family/carer) can self-inject, carry a steroid emergency card + MedicAlert, and never abruptly stop steroids. Flag the medical record. Coordinate steroid cover for procedures and dental work.
Step 9 · monitoring & safety-net
Step 9 · Monitoring & safety-netReview & when to escalate
Annual review of replacement dose, weight/BP (incl. postural), U&E, and sick-day-rule confidence; renew the emergency kit before expiry. 999 + IM hydrocortisone for vomiting, collapse, severe weakness or any acute illness with shock — anyone can give the injection. Treat first, confirm later.
⚠️ Never delay steroids for tests (NG243): give hydrocortisone 100mg IM/IV and fluids first. Prevention beats treatment — flag the notes of everyone with adrenal insufficiency, ensure they're confident with sick-day rules, and that they carry an emergency IM hydrocortisone kit + steroid card.
1
Safety

Adrenal Crisis — Recognise & Treat Before Confirming the Diagnosis

Adrenal (Addisonian) crisis is the can’t-miss emergency. Treat on clinical suspicion — do NOT wait for biochemistry. Death is from hypovolaemic shock and hyperkalaemia.

Shock + known/possible adrenal insufficiency Hypotension, collapse, vomiting, abdominal pain, fever, confusion → 999 + immediate IM/IV hydrocortisone 100 mg.
Hyponatraemia + hyperkalaemia Low Na⁺ with raised K⁺ (± hypoglycaemia, mild hypercalcaemia) is the classic biochemical signature — treat empirically while confirming.
Intercurrent illness / missed steroids Any patient on long-term steroids who is vomiting, septic or has stopped their steroid → crisis risk. Give parenteral hydrocortisone.
Waterhouse-Friderichsen Adrenal haemorrhage in meningococcal/severe sepsis → purpura + shock → 999.
Hypoglycaemia Especially in children/secondary adrenal insufficiency → treat with IV glucose + hydrocortisone.
New presentation can BE the crisis Up to 50% of Addison’s is diagnosed at first crisis — keep a low threshold in unexplained shock.
Adrenal crisis carries significant mortality and is reversible with timely steroid. Immediate management is IV/IM hydrocortisone 100 mg, aggressive IV 0.9% saline rehydration, treat hypoglycaemia, and identify/treat the precipitant. Take a random cortisol (and ideally ACTH) before steroid if it does not delay treatment — but treatment always comes first.
2
Diagnose

History — The Insidious Picture & Its Mimics

Chronic primary adrenal insufficiency is notoriously non-specific and frequently mislabelled as depression, CFS, anorexia or IBS for months to years.

Core symptoms
Profound fatigue, weakness, anorexia, weight loss, nausea, dizziness. Salt craving is highly suggestive of mineralocorticoid deficiency.
Postural symptoms
Dizziness/lightheadedness on standing → postural hypotension from aldosterone deficiency and volume depletion.
Hyperpigmentation
Primary (Addison’s) only: ACTH-driven pigmentation of palmar creases, buccal mucosa, scars, pressure areas. Absent in secondary (pituitary) causes.
Autoimmune clues
Personal/family history of type 1 diabetes, autoimmune thyroid disease, vitiligo, pernicious anaemia, coeliac → autoimmune polyglandular syndrome.
Other causes
TB (commonest worldwide), adrenal metastases/bilateral haemorrhage, adrenalectomy, drugs (ketoconazole, etomidate), HIV, infiltrative disease.
Steroid history
Abrupt withdrawal of long-term oral/inhaled/topical steroids → secondary (tertiary) adrenal insufficiency. Ask explicitly about steroid use.
The mean delay to diagnosing Addison’s exceeds a year because symptoms are vague. Salt craving and hyperpigmentation are the two most discriminating clinical features for primary disease; their absence does not exclude it. Recognising the autoimmune cluster (Schmidt syndrome) shortens the diagnostic journey.
3
Diagnose

Examination

Look specifically for the signs that separate primary from secondary, and for evidence of associated autoimmune disease.

Blood pressure
Postural hypotension (drop >20 mmHg systolic). Persistent hypotension in chronic disease.
Pigmentation
Palmar creases, buccal/gingival mucosa, recent scars, knuckles, pressure points — primary disease only.
Vitiligo
Depigmented patches → autoimmune association.
Hydration / volume
Dry mucous membranes, reduced skin turgor, tachycardia → volume depletion.
Weight / muscle
Weight loss, muscle wasting, general debility.
Thyroid / other endocrine
Goitre or signs of hypo/hyperthyroidism (polyglandular syndrome).
Hyperpigmentation reflects elevated ACTH and pro-opiomelanocortin (POMC)-derived peptides in primary adrenal failure, and its distribution at sun-exposed and pressure sites is characteristic. Its presence localises the lesion to the adrenal gland rather than the pituitary.
4
Diagnose

Investigations — Confirm & Localise

Confirm cortisol deficiency, then localise (primary vs secondary) and seek the cause. Do not let testing delay treatment in a crisis.

9am serum cortisol First-line
Low (<100 nmol/L) strongly suggests insufficiency; >430–500 nmol/L makes it unlikely; intermediate → Short Synacthen Test.
Short Synacthen Test Confirmatory
250 µg tetracosactide; measure cortisol at 0 and 30 min. Failure to rise above threshold (~>430–550 nmol/L lab-dependent) confirms adrenal insufficiency.
Plasma ACTH
High ACTH + low cortisol = primary (Addison’s). Low/inappropriately normal ACTH = secondary (pituitary/hypothalamic).
U&E / glucose
Hyponatraemia, hyperkalaemia, hypoglycaemia, mild hypercalcaemia, raised urea.
Adrenal autoantibodies
21-hydroxylase antibodies positive in autoimmune Addison’s (commonest UK cause).
Cause workup
If antibody-negative: adrenal CT (TB, haemorrhage, metastases, infiltration), TB screen. If secondary: pituitary MRI + full pituitary axis.
Renin / aldosterone
High renin with low aldosterone confirms mineralocorticoid deficiency in primary disease.
The Short Synacthen Test is the definitive primary-care-accessible confirmatory test. Pairing cortisol with ACTH localises the defect, and 21-hydroxylase antibodies identify the autoimmune aetiology that accounts for the majority of UK cases. Antibody-negative disease mandates imaging to exclude TB, bilateral metastases, haemorrhage or infiltration.
5
Treat

Replacement Therapy

Lifelong glucocorticoid and (in primary disease) mineralocorticoid replacement, titrated clinically. Under-replacement risks crisis; over-replacement risks Cushingoid harm.

GlucocorticoidHydrocortisone 15–25 mg/day in 2–3 divided doses, largest on waking to mimic the circadian rhythm (e.g. 10/5/5 mg). Some use prednisolone OD. Titrate to wellbeing, not to random cortisol.
MineralocorticoidFludrocortisone 50–200 µg OD in primary disease only. Titrate to BP, postural drop, electrolytes and plasma renin. Not needed in secondary insufficiency.
Androgen (selected)DHEA may be considered in women with impaired wellbeing/libido despite adequate gluco/mineralocorticoid — specialist-led, not routine.
MonitoringClinical review of weight, BP, energy, pigmentation; U&E and renin for fludrocortisone dosing. Avoid over-replacement (weight gain, hypertension, osteoporosis, dysglycaemia).
Replacement aims to reproduce physiological cortisol secretion; the morning-loaded divided regimen reduces fatigue. Fludrocortisone is only required in primary disease because secondary insufficiency preserves the renin-angiotensin-aldosterone axis. Dose adequacy is judged clinically and biochemically, never by a single random cortisol.
6
Safety

Sick-Day Rules & Crisis Prevention — Critical Patient Education

The most examinable, life-saving element. Every patient must know the sick-day rules and carry emergency steroid.

Sick-day rule 1 (oral)
Double the oral glucocorticoid dose during fever/intercurrent illness or significant infection until recovered.
Sick-day rule 2 (parenteral)
Vomiting, diarrhoea, or unable to take/keep down tablets → IM hydrocortisone (emergency injection kit) and seek urgent medical help.
Procedures
Surgery, major dental work, colonoscopy prep → peri-procedure parenteral steroid cover per protocol.
Steroid Emergency Card
Issue the NHS Steroid Emergency Card + MedicAlert/bracelet. Ensure documented on records and prescriptions.
Emergency kit
Provide a hydrocortisone IM injection kit and train patient/family to use it. Replace before expiry.
Never stop abruptly
Sudden cessation precipitates crisis. Reinforce adherence at every review.
Adrenal crisis is largely preventable through patient education. The 2020 NHS Steroid Emergency Card initiative standardised peri-operative and sick-day management. The SCA examiner expects explicit, structured safety-netting: double oral dose for fever, switch to IM hydrocortisone if vomiting, and call for help — delivered in plain language the patient can act on.
7
Refer

Referral Pathways

Suspected adrenal insufficiency is an endocrinology diagnosis — refer for confirmation and lifelong supervision; manage crises as emergencies.

999 / acute medicine
Suspected adrenal crisis — admit after first-dose parenteral hydrocortisone and IV fluids.
Urgent endocrinology
New biochemical/clinical suspicion (low 9am cortisol, abnormal Synacthen, suggestive electrolytes) — for confirmation, cause workup and treatment initiation.
Pituitary / neurosurgery
Secondary insufficiency with pituitary lesion on MRI — joint endocrine/neurosurgical care.
Oncology
Bilateral adrenal metastases identified on imaging as the cause — manage primary malignancy via the appropriate cancer pathway.
Primary care role
Repeat prescriptions, sick-day reinforcement, immunisations, monitoring, and coordinating annual specialist review.
Although diagnosis and stabilisation are specialist-led, primary care is central to safe long-term care: ensuring uninterrupted steroid supply, reinforcing sick-day rules, and recognising decompensation early. Bilateral adrenal metastases (e.g. from lung cancer) are an important non-autoimmune cause and route into the relevant cancer pathway.
8
Lifestyle

Living With Adrenal Insufficiency

Adherence Lifelong, non-negotiable medication. Use reminders/dosette boxes; never run out — order in advance and when travelling.
Identification Carry the Steroid Emergency Card and wear a MedicAlert bracelet at all times.
Travel Carry extra medication and an IM hydrocortisone kit in hand luggage with a doctor’s letter; know how to access care abroad.
Vaccination & infection Keep immunisations up to date; treat infections promptly and apply sick-day rules early.
Family training Teach family/carers to recognise crisis and administer emergency IM hydrocortisone.
Support Signpost to the Addison’s Disease Self-Help Group (ADSHG) for patient resources and peer support.
Self-management is the cornerstone of preventing crisis. Patients who reliably apply sick-day rules and carry emergency steroid have far fewer life-threatening episodes. Empowering family members to inject hydrocortisone provides a critical safety margin during severe illness or vomiting.
9
Safety

Follow-Up & Monitoring

Each review
Assess wellbeing, energy, weight, BP (lying/standing), pigmentation. Confirm sick-day knowledge and that emergency kit/card are current.
Fludrocortisone dosing
Check U&E and (where available) plasma renin; adjust to normalise BP, postural drop and electrolytes.
Over-replacement screen
Watch for weight gain, hypertension, dysglycaemia, osteoporosis — minimise glucocorticoid dose accordingly.
Associated autoimmune disease
Periodically screen for thyroid disease, B12 deficiency, coeliac, type 1 diabetes in autoimmune Addison’s.
Annual specialist review
Coordinate endocrinology follow-up; bone health assessment as indicated.
Safety-net
Any acute illness/vomiting → sick-day rules + urgent help. Re-educate at every contact.
Long-term monitoring balances the harms of under- and over-replacement and detects the additional autoimmune conditions that cluster with autoimmune Addison’s. Repeated reinforcement of sick-day rules at every encounter is the highest-yield safety intervention in chronic care.
Educational use only. Pathway based on: NICE CKS Addison’s disease, Society for Endocrinology emergency guidance for acute adrenal insufficiency, NHS England Steroid Emergency Card (2020), Endocrine Society clinical practice guidelines. Always adapt to individual patient context, co-morbidities and local protocols.