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Approaching endocrine symptoms and hormone feedback loops

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Escalate

Shock with vomiting or hyperkalaemia, severe hypo- or hyperglycaemia with ketones or altered consciousness, profound sodium disturbance with seizure, severe calcium disturbance with arrhythmia, new visual loss with sudden headache, thyroid-related hyperthermia and delirium, or hypothermia with bradycardia requires immediate ABCDE care. Take useful endocrine samples when this causes no delay, but do not withhold hydrocortisone, glucose, fluids or other life-saving treatment while waiting for hormone results.

Synopsis

Convert non-specific symptoms into an anatomical endocrine hypothesis, interpret paired hormones through feedback physiology, and recognise results or presentations that need immediate treatment or specialist escalation.

  • Endocrine symptoms such as fatigue, weight change, thirst, menstrual disturbance and palpitations are common; specificity comes from tempo, associated signs, medicines and a coherent physiological pattern.
  • Interpret a target-gland hormone with its controlling hormone whenever the axis permits: an isolated number often cannot distinguish primary gland disease from hypothalamic or pituitary disease.
  • In primary target-gland failure the end hormone is low and the trophic hormone usually rises; in central failure the trophic hormone is low or inappropriately normal for the low end hormone.

Key red flags

Central endocrine failure

A low end hormone with a low or merely normal trophic hormone is discordant and can indicate hypothalamic or pituitary disease, particularly when several axes or visual symptoms coexist.

Investigation priorities

01
Paired TSH and free T4First step

Assess the thyroid axis and distinguish primary thyroid dysfunction from a potentially central pattern.

Management branches

First encounterBuild an axis hypothesis

Non-specific symptoms raise the possibility of endocrine disease.

  1. Define tempo, episodic triggers, weight and fluid balance, reproductive symptoms, family syndromes and every prescribed, injected, inhaled, topical and non-prescription hormone-active product.
  2. Examine physiology and targeted signs, separating an acutely unstable presentation from a stable outpatient question before ordering broad tests.
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Sources and review status4 sources · checked 27 Aug 2026 · clinical review pending
Sources

Sources and review status

National guidance is shown before implementation-dependent detail. Typical adult dose examples remain subject to patient factors, contraindications and the live BNF or specialist protocol. Source check completed 27 Aug 2026; clinical approval remains outstanding.

Authoring stateRapid draftClinical stateAwaiting reviewJurisdictionUnited Kingdom