Why this topic matters in emergency medical care
Hormones regulate glucose, blood pressure, temperature, fluid balance, calcium, stress responses, growth and reproduction. A small error with an endocrine medicine can therefore produce rapid neurological, cardiovascular or metabolic deterioration. The emergency medical technician (EMT) must recognise endocrine patterns early, obtain a safe medication history, perform immediate supportive care, prevent avoidable harm and communicate clearly with the receiving team.
This lesson develops the pharmacology behind common endocrine medicines and links each class to practical pre-hospital and emergency-department decisions. It is an educational guide for supervised practice; follow the current Uganda Ministry of Health guidance, facility protocols, prescriber instructions and medicine-specific product information.
Learning outcomes
By the end of this lesson, the learner should be able to:
- Explain how the hypothalamus, pituitary, thyroid, parathyroids, adrenals, pancreas and gonads coordinate endocrine function.
- Classify endocrine medicines by hormone replaced, receptor targeted, enzyme inhibited or metabolic pathway changed.
- Compare insulin preparations, non-insulin glucose-lowering medicines and emergency glucose-raising medicines.
- Recognise and initially manage hypoglycaemia, diabetic ketoacidosis (DKA), hyperosmolar hyperglycaemic state (HHS), thyroid storm, myxoedema coma, adrenal crisis and severe hypercalcaemia.
- Apply safe principles of dose checking, route selection, preparation, administration, monitoring, documentation and handover.
- Identify contraindications, interactions, high-risk populations and medicines that must not be stopped abruptly.
- Use structured clinical reasoning in realistic EMT scenarios and answer examination-style revision questions.
1. Endocrine physiology and medicine targets
The endocrine system communicates through hormones released into the bloodstream. Peptide hormones (for example insulin, glucagon and antidiuretic hormone) usually bind cell-surface receptors and act quickly. Steroid hormones (for example cortisol, aldosterone and sex hormones) cross cell membranes and alter gene transcription. Thyroid hormones enter cells and change metabolic activity over hours to days. Pharmacological treatment may replace a deficient hormone, mimic or block a hormone, alter its synthesis, change receptor signalling or remove an excess effect.
| Gland or axis | Major hormones | Core physiological effects | Emergency relevance |
|---|---|---|---|
| Hypothalamus–pituitary | CRH, TRH, GnRH, GHRH, ACTH, TSH, LH, FSH, GH, prolactin; ADH from posterior pituitary | Controls downstream glands, growth, reproduction, water balance and stress response | Pituitary failure can cause adrenal insufficiency, hyponatraemia, hypoglycaemia and altered consciousness. |
| Thyroid | Thyroxine (T4), triiodothyronine (T3), calcitonin | Sets basal metabolic rate, heat production, cardiac sensitivity to catecholamines and bone turnover | Excess may cause thyroid storm; severe deficiency may cause myxoedema coma, hypothermia and bradycardia. |
| Parathyroids | Parathyroid hormone (PTH) | Raises serum calcium, activates vitamin D and increases renal calcium conservation | Hypercalcaemia can cause dehydration, confusion, arrhythmia and renal injury; hypocalcaemia can cause tetany or seizures. |
| Adrenal cortex | Cortisol, aldosterone, adrenal androgens | Stress adaptation, vascular tone, glucose availability, sodium retention and potassium excretion | Adrenal crisis presents with shock, vomiting, abdominal pain, hypoglycaemia and electrolyte disturbance. |
| Adrenal medulla | Adrenaline and noradrenaline | Rapid sympathetic response: heart rate, contractility, vasoconstriction and bronchodilation | These drugs are life-saving when correctly indicated but can cause severe tachyarrhythmia or ischaemia if misused. |
| Pancreatic islets | Insulin, glucagon, somatostatin | Balances glucose storage, mobilisation and nutrient metabolism | Insulin excess causes hypoglycaemia; insulin deficiency causes DKA or HHS. |
| Bone–kidney–vitamin D axis | Calcium, phosphate, vitamin D, PTH | Maintains neuromuscular function and skeletal mineralisation | Calcium abnormalities may produce weakness, paraesthesia, seizures or ECG changes. |
EMT safety rule: an endocrine medicine may correct a laboratory value while worsening the patient’s immediate physiology. Always reassess airway, breathing, circulation, mental status, temperature, glucose, ECG and perfusion before and after giving or withholding a medicine.
2. General principles of endocrine pharmacology
2.1 Replacement, suppression and receptor modification
- Replacement: insulin for absolute insulin deficiency, levothyroxine for thyroid hormone deficiency and hydrocortisone for cortisol deficiency.
- Suppression or blockade: antithyroid medicines reduce new thyroid hormone synthesis; glucocorticoid antagonists block cortisol effects; somatostatin analogues suppress selected pituitary and gastrointestinal hormones.
- Receptor or pathway modification: GLP-1 receptor agonists increase glucose-dependent insulin secretion and reduce appetite; SGLT2 inhibitors promote urinary glucose loss; bisphosphonates reduce osteoclast activity.
- Emergency antagonism or rescue: glucagon and concentrated glucose reverse severe hypoglycaemia; calcium may stabilise the myocardium in selected hyperkalaemic or hypocalcaemic emergencies.
2.2 Pharmacokinetics that change emergency decisions
| Principle | What it means | Why the EMT cares |
|---|---|---|
| Onset and peak | Time until an effect begins and reaches its maximum | Rapid-acting insulin can cause early hypoglycaemia; long-acting insulin may continue acting after the patient appears improved. |
| Half-life and duration | Time for concentration to fall and clinical effect to wear off | Recurrent hypoglycaemia may occur after sulfonylurea or long-acting insulin exposure. |
| Route and bioavailability | Amount reaching systemic circulation depends on IV, IM, subcutaneous, oral or enteral delivery | Shock, vomiting or poor perfusion can make oral or subcutaneous absorption unreliable. |
| Protein binding and distribution | Only unbound drug is readily active; altered albumin or fluid status changes distribution | Critical illness and kidney disease can increase toxicity from highly protein-bound or renally cleared medicines. |
| Hepatic metabolism | Liver enzymes transform many medicines before elimination | Severe hepatic disease may prolong effects and increase hypoglycaemia risk. |
| Renal clearance | Kidneys excrete drug or active metabolites | Insulin, metformin metabolites and several glucose-lowering medicines require extra caution in kidney impairment. |
3. Endocrine medicines: a practical classification
| Group | Representative medicines | Main emergency or clinical use | High-risk problem |
|---|---|---|---|
| Insulins | Regular/soluble, NPH, glargine, detemir, degludec, lispro, aspart | Type 1 diabetes, selected type 2 diabetes, DKA and HHS protocols | Hypoglycaemia, hypokalaemia, wrong product or wrong timing |
| Insulin secretagogues | Gliclazide, glimepiride, glibenclamide | Type 2 diabetes when pancreatic beta cells still produce insulin | Prolonged or recurrent hypoglycaemia, especially in older adults or renal disease |
| Insulin sensitiser | Metformin | First-line type 2 diabetes therapy in many patients | Lactic acidosis risk in severe hypoxia, shock, sepsis or renal failure |
| Incretin-based medicines | GLP-1 receptor agonists; DPP-4 inhibitors | Glucose control with low hypoglycaemia risk when used alone | Vomiting, dehydration, pancreatitis warning symptoms or delayed gastric emptying |
| SGLT2 inhibitors | Dapagliflozin, empagliflozin, canagliflozin | Type 2 diabetes; cardio-renal benefit in selected patients | Euglycaemic DKA, dehydration, genital infection and peri-operative risk |
| Thyroid replacement | Levothyroxine; liothyronine in selected specialist situations | Hypothyroidism and myxoedema coma protocols | Over-replacement may precipitate angina, atrial fibrillation or thyroid storm. |
| Antithyroid medicines | Propylthiouracil, methimazole/carbimazole, iodide | Thyrotoxicosis and thyroid storm treatment plans | Agranulocytosis, hepatotoxicity, and incorrect timing of iodide |
| Adrenal replacement | Hydrocortisone, prednisolone, fludrocortisone | Adrenal insufficiency and adrenal crisis | Failure to stress-dose can be fatal; abrupt chronic steroid withdrawal is dangerous. |
| Calcium and vitamin D medicines | Calcium gluconate, calcium chloride, calcitriol, cholecalciferol | Hypocalcaemia, tetany, selected cardiac membrane-stabilisation indications | Extravasation injury, arrhythmia or hypercalcaemia |
| Bone medicines | Bisphosphonates, denosumab | Hypercalcaemia of malignancy and osteoporosis management | Renal injury, hypocalcaemia, oesophageal irritation or jaw osteonecrosis |
4. Insulin preparations and safe insulin practice
Insulin lowers plasma glucose by increasing cellular glucose uptake and reducing hepatic glucose production. It also shifts potassium into cells. This is why insulin is life-saving in DKA but can produce dangerous hypoglycaemia or hypokalaemia if glucose and electrolytes are not monitored. Insulin is a high-alert medicine: verify the product, concentration, dose, route, timing, patient identity and recent glucose before administration.
| Insulin category | Examples | Typical profile (approximate) | Clinical teaching point |
|---|---|---|---|
| Rapid-acting analogue | Lispro, aspart, glulisine | Onset about 10–20 min; short duration | Usually coordinated with meals; hypoglycaemia occurs if food is delayed or missed. |
| Short-acting soluble human insulin | Regular insulin | Slower onset than analogues; can be used IV in monitored DKA protocols | Only use IV regular insulin when the local protocol and trained clinician specify it. |
| Intermediate-acting | NPH/isophane | Distinct peak; longer duration | Peak-related hypoglycaemia may occur overnight or between meals. |
| Long-acting basal | Glargine, detemir, degludec | Flat or near-flat basal effect; long duration | Do not mix glargine or detemir in the same syringe; never omit basal insulin in type 1 diabetes without specialist direction. |
| Premixed formulations | Human or analogue combinations | Fixed basal and meal components | Less flexible when meal size or timing changes; confirm the exact mixture. |
4.1 Insulin administration checklist
- Confirm the order: insulin name, concentration (for example U-100), dose, route, timing and indication.
- Identify the patient: use two identifiers and ask about allergies, diabetes type, last meal and last insulin dose.
- Check the product: inspect expiry, appearance and storage. Cloudiness is expected for some suspensions such as NPH but not for clear soluble insulin.
- Check glucose and ketones: document capillary glucose; obtain ketones when DKA is possible and the equipment/protocol is available.
- Check potassium and renal status in monitored care: insulin can worsen hypokalaemia; severe hypokalaemia generally requires correction before insulin in DKA protocols.
- Use the correct device: an insulin syringe or pen marked in insulin units. Never estimate units with a non-insulin syringe.
- Administer and observe: use correct subcutaneous sites and rotate them; IV insulin requires a pump or controlled infusion and independent double-check.
- Reassess: repeat glucose at the protocol interval, watch for sweating, tremor, confusion, weakness, seizures or arrhythmia, and document response.
“RIGHT INSULIN” safety mnemonic
Recheck patient and prescription · Insulin name and concentration · Glucose/ketones · Hypokalaemia risk · Timing with food
Insulin device · Needle/site · Second checker for high-alert doses · Understand onset/peak · Look for hypoglycaemia · Inform and document · Next glucose check
5. Non-insulin glucose-lowering medicines
| Class | How it works | Benefits | Important adverse effects and emergency cautions |
|---|---|---|---|
| Metformin (biguanide) | Reduces hepatic gluconeogenesis and improves insulin sensitivity | Effective, inexpensive and does not usually cause hypoglycaemia alone | Gastrointestinal upset; hold or seek prescriber review in shock, severe hypoxia, sepsis, acute kidney injury or major contrast-related risk because lactic acidosis is uncommon but serious. |
| Sulfonylureas | Stimulate pancreatic beta-cell insulin release regardless of current glucose | Lower glucose rapidly and are widely available | Prolonged hypoglycaemia; risk rises with missed meals, renal/hepatic impairment, alcohol or older age. Recurrent episodes need observation and medical review. |
| DPP-4 inhibitors | Prolong endogenous incretin action and glucose-dependent insulin secretion | Low hypoglycaemia risk when used alone; oral dosing | Dose adjustment may be needed in kidney disease; assess for pancreatitis symptoms and drug interactions. |
| GLP-1 receptor agonists | Increase glucose-dependent insulin, reduce glucagon, slow gastric emptying and increase satiety | Good glucose and weight effects; low hypoglycaemia risk without insulin or secretagogue | Nausea/vomiting and dehydration; consider aspiration risk from delayed gastric emptying. Severe persistent abdominal pain requires urgent assessment. |
| SGLT2 inhibitors | Reduce proximal renal glucose reabsorption, causing glucosuria and mild natriuresis | Cardio-renal benefits in selected patients | Genital/urinary infections, volume depletion and euglycaemic DKA. A near-normal glucose does not exclude DKA in a patient taking an SGLT2 inhibitor. |
| Thiazolidinediones | Activate PPAR-gamma and improve insulin sensitivity | Durable insulin-sensitising effect | Fluid retention, weight gain and heart-failure worsening; not an acute rescue medicine. |
| Alpha-glucosidase inhibitors | Delay intestinal carbohydrate breakdown and absorption | Reduce post-meal glucose rise | Flatulence and diarrhoea; if hypoglycaemia occurs with another medicine, use glucose rather than sucrose. |
6. Hypoglycaemia: recognise, treat and prevent recurrence
Hypoglycaemia is a time-critical glucose emergency. Symptoms result from autonomic activation and inadequate glucose delivery to the brain: sweating, tremor, palpitations, hunger, anxiety, irritability, confusion, abnormal behaviour, seizures and coma. In a patient with altered mental status, check glucose early, but do not delay airway and breathing support.
| Patient state | Immediate approach | Examples of treatment | Reassessment |
|---|---|---|---|
| Awake, protecting airway, able to swallow | Give fast-acting oral carbohydrate; do not give food or drink to a drowsy patient. | Glucose gel/tablets or a measured sugary drink according to local protocol; follow with longer-acting carbohydrate once recovered. | Recheck glucose after about 10–15 minutes; repeat treatment if still low, then investigate cause. |
| Confused, seizing, unconscious or unsafe swallow | Place in recovery position if breathing, suction as needed, give oxygen when indicated, obtain IV/IO access and call for advanced support. | IV dextrose/glucose using local concentration and dose, or IM/SC glucagon when IV access is delayed or unavailable and the protocol permits. | Recheck frequently; protect against recurrent hypoglycaemia, especially after sulfonylurea or long-acting insulin. |
| Persistent or recurrent episodes | Search for medication error, renal failure, sepsis, liver failure, adrenal insufficiency, starvation or alcohol. | May require dextrose infusion, prolonged observation and specialist treatment. | Document times, measured values, treatment and response; provide prevention education before discharge. |
Never “feed” an unconscious patient. Oral fluids or sugar can be aspirated. Protect the airway, use a suitable parenteral rescue medicine under protocol and reassess continuously.
7. Diabetic ketoacidosis (DKA) and hyperosmolar hyperglycaemic state (HHS)
DKA results from insufficient effective insulin with increased ketone production and metabolic acidosis. HHS is dominated by extreme hyperglycaemia, hyperosmolality and profound dehydration with little or no significant ketosis. They can overlap. Infection, missed insulin, myocardial infarction, stroke, pancreatitis, corticosteroids, new diabetes and SGLT2 inhibitors are important triggers.
| Feature | DKA | HHS | EMT implication |
|---|---|---|---|
| Typical onset | Hours to a few days | Days to weeks | Do not dismiss gradual confusion or dehydration as simple weakness. |
| Glucose | Raised, but may be only moderately elevated in euglycaemic DKA | Usually very high | Use ketones and clinical context; glucose alone cannot exclude DKA. |
| Ketones/acidosis | Prominent ketonaemia and metabolic acidosis | Minimal ketones; hyperosmolality dominates | Check capillary ketones if available and report results. |
| Neurology | Alertness varies; Kussmaul breathing may occur | Marked confusion, seizures or coma more common | Assess GCS/AVPU, airway, aspiration risk and stroke mimics. |
| Fluid deficit | Substantial | Often extreme | Establish IV access, monitor perfusion and follow a controlled fluid protocol; beware heart or kidney failure. |
7.1 Pre-hospital priorities
- Perform an ABCDE assessment, check glucose, temperature, mental status, respiratory pattern, blood pressure, pulse and oxygen saturation.
- Look for triggers: infection, missed insulin, medication change, pregnancy, chest pain, stroke symptoms, abdominal pain, vomiting or SGLT2-inhibitor use.
- Establish IV access where trained and permitted; obtain ECG and monitor rhythm if available.
- Begin isotonic fluid resuscitation only according to local protocol and reassess frequently, particularly in older adults, heart failure or kidney disease.
- Do not give an insulin bolus casually. DKA insulin therapy requires potassium assessment, controlled infusion and serial laboratory monitoring.
- Transport urgently to a facility able to measure electrolytes, venous/arterial blood gas, ketones, renal function and osmolality.
8. Thyroid medicines
8.1 Levothyroxine and thyroid hormone replacement
Levothyroxine is synthetic T4. Peripheral tissues convert T4 to the active hormone T3. It is usually taken orally on an empty stomach at a consistent time. Absorption falls when taken with iron, calcium, antacids, some binding agents or certain foods. A patient who suddenly develops palpitations, chest pain, tremor, sweating or confusion after a dose change may be over-replaced or developing another acute illness.
- Do not use a normal thyroid-stimulating hormone (TSH) value as an immediate measure of response in a critically ill patient; clinical context and free hormone results guide specialist decisions.
- Older adults and people with coronary disease usually require cautious dose increases because thyroid hormone raises myocardial oxygen demand and can precipitate angina or atrial fibrillation.
- In suspected myxoedema coma, airway support, active but controlled warming, glucose assessment, infection search and stress-dose corticosteroid coverage are priorities alongside specialist thyroid replacement.
8.2 Antithyroid medicines
| Medicine/class | Mechanism | Uses | Safety warnings |
|---|---|---|---|
| Methimazole/carbimazole | Inhibits thyroid peroxidase, reducing organification and coupling | Most non-pregnancy thyrotoxicosis; specialist treatment plans | Fever or sore throat may indicate agranulocytosis; jaundice or dark urine may indicate liver injury. Seek urgent review. |
| Propylthiouracil (PTU) | Inhibits thyroid peroxidase and reduces peripheral T4-to-T3 conversion | Selected thyroid storm protocols and some pregnancy situations under specialist direction | Severe hepatotoxicity risk; do not substitute without prescriber guidance. |
| Iodide (potassium iodide or Lugol solution) | Rapidly inhibits thyroid hormone release and organification after an antithyroid drug | Thyroid storm or pre-operative preparation in selected protocols | Timing matters: giving iodide before blocking synthesis can provide substrate for new hormone production. |
| Beta-blocker | Controls adrenergic manifestations; propranolol also reduces T4-to-T3 conversion at higher doses | Tremor, tachycardia and hypertension in thyrotoxicosis | Bronchospasm, bradycardia, heart failure or shock may make it unsafe; treat the physiology, not just the pulse. |
9. Thyroid emergencies
9.1 Thyroid storm
Thyroid storm is decompensated thyrotoxicosis with fever, marked tachycardia, agitation or delirium, gastrointestinal symptoms, heart failure or shock. It is commonly triggered by infection, surgery, trauma, childbirth, stopping antithyroid medication or iodine exposure. There is no single bedside test that confirms it immediately; treat the clinical syndrome while seeking expert help.
- ABCDE assessment, cardiac monitoring, IV access, glucose, temperature, ECG and urgent transport.
- Support oxygenation and circulation; use cautious fluids if heart failure is present and treat severe hyperthermia with cooling measures.
- Search for and treat the trigger, especially infection, myocardial infarction, pulmonary embolism or medication interruption.
- Specialist therapy commonly combines an antithyroid medicine, then iodide after an appropriate interval, a beta-blocker when haemodynamically safe, and glucocorticoid support.
- Avoid aspirin for fever in suspected thyroid storm unless specifically directed, because it can increase free thyroid hormone; use local antipyretic guidance.
9.2 Myxoedema coma
Myxoedema coma is severe decompensated hypothyroidism, often precipitated by infection, cold exposure, sedatives, stroke, trauma or stopping thyroid replacement. Patients may have hypothermia, bradycardia, hypotension, hypoventilation, hyponatraemia, hypoglycaemia and reduced consciousness; the name is misleading because many are not literally comatose.
- Protect the airway early; hypoventilation and carbon dioxide retention may be prominent.
- Handle gently and avoid rapid peripheral warming that can worsen vasodilation and hypotension.
- Check glucose immediately and correct hypoglycaemia; obtain ECG and electrolytes.
- Give stress-dose hydrocortisone when adrenal insufficiency cannot be excluded, then specialist-directed thyroid hormone replacement.
- Look for infection even without fever; severe hypothyroidism can blunt the inflammatory response.
10. Adrenal medicines and corticosteroid safety
10.1 Corticosteroid classes
| Medicine | Relative glucocorticoid effect | Mineralocorticoid effect | Practical use |
|---|---|---|---|
| Hydrocortisone | Short-acting, physiologic replacement and stress dosing | Meaningful | Preferred emergency medicine for suspected adrenal crisis in many protocols. |
| Prednisolone/prednisone | Intermediate-acting | Lower than hydrocortisone | Chronic replacement or inflammatory disease; conversion must be prescribed. |
| Dexamethasone | Long-acting and potent | Minimal | Useful when a glucocorticoid effect is needed without mineralocorticoid activity; specialist selection matters. |
| Fludrocortisone | Minimal glucocorticoid effect | Strong | Mineralocorticoid replacement in primary adrenal insufficiency; monitor blood pressure and electrolytes. |
10.2 Adrenal crisis
Adrenal crisis is inadequate cortisol during physiological stress. Suspect it in a person with known adrenal insufficiency, chronic steroid use, pituitary disease or recent steroid withdrawal who develops unexplained hypotension, collapse, vomiting, abdominal pain, weakness, confusion, fever, hypoglycaemia or hyponatraemia. Primary disease may also cause hyperkalaemia and skin hyperpigmentation.
Clinical reasoning example
A patient with Addison disease has diarrhoea, vomiting and dizziness after several days of infection. The key danger is not simply dehydration: the patient cannot absorb oral hydrocortisone and may have lost the cortisol surge required to maintain vascular tone. Give emergency parenteral hydrocortisone under protocol, begin supportive resuscitation and arrange immediate hospital care.
- Call for advanced help and perform ABCDE; place the patient supine if tolerated and monitor ECG, blood pressure, glucose and temperature.
- Give parenteral hydrocortisone immediately when adrenal crisis is suspected according to the authorised local dose and route. Do not delay for cortisol results.
- Give isotonic fluid for shock, reassessing lungs, perfusion and urine output; add dextrose when hypoglycaemia is present.
- Search for triggers such as infection, gastroenteritis, trauma, surgery, missed doses or abrupt steroid cessation.
- Communicate the last steroid dose, emergency injection, fluid volume, glucose trend, blood pressure and response during handover.
Never stop long-term systemic corticosteroids abruptly. Suppression of the hypothalamic–pituitary–adrenal axis can persist after the original illness improves. Tapering and stress-dose plans must be clinician-directed.
11. Calcium, vitamin D and bone medicines
| Medicine/class | Mechanism or purpose | Emergency relevance | Key precautions |
|---|---|---|---|
| Calcium gluconate | Raises extracellular calcium and stabilises excitable membranes | Symptomatic hypocalcaemia; selected hyperkalaemia or calcium-channel-blocker toxicity protocols | Continuous ECG and local protocol; extravasation can injure tissue. |
| Calcium chloride | More elemental calcium per volume than gluconate | Selected resuscitation or toxicology indications under advanced protocols | Prefer a secure central line when required; severe extravasation risk. |
| Vitamin D/calcitriol | Improves intestinal calcium absorption; calcitriol acts rapidly | Chronic deficiency or hypoparathyroidism management | Overdose can cause hypercalcaemia, confusion, polyuria and renal injury. |
| Bisphosphonates | Inhibit osteoclast-mediated bone resorption | Hypercalcaemia of malignancy and skeletal disease; not immediate first-line resuscitation | Renal function, infusion rate and hypocalcaemia risk must be monitored. |
| Denosumab | Inhibits RANKL and osteoclast formation | Selected osteoporosis or malignancy indications | Delayed hypocalcaemia, especially with renal impairment; maintain follow-up. |
12. Medication safety in endocrine emergencies
12.1 The endocrine medication history
- Ask the exact medicine name, strength, formulation, route, usual time and last dose.
- Ask about insulin pens, pumps, continuous glucose monitors, glucose tablets, glucagon kits, steroid cards or emergency injection kits.
- Ask whether doses were missed, doubled, changed recently, vomited, taken with food or stopped because the patient felt better.
- Identify over-the-counter products and supplements: calcium, iron, iodine-containing products, herbal remedies, weight-loss products and “energy” preparations.
- Check pregnancy or breastfeeding, kidney/liver disease, heart failure, thyroid disease, adrenal disease, alcohol use and allergies.
- Bring medicine containers, a photograph of the prescription or the patient’s treatment card to hospital when possible.
12.2 Look-alike and sound-alike risks
| Risk | Example of error | Prevention |
|---|---|---|
| Units versus millilitres | Drawing up insulin units in a non-insulin syringe | Use the labelled insulin syringe/pen; independently verify concentration. |
| Product confusion | Mixing up rapid-acting and long-acting insulin | Read the label three times and use a second checker for high-alert doses. |
| Concentration confusion | Substituting U-200/U-300/U-500 for U-100 without recalculation | Use only the matching device and written prescription; never convert mentally during an emergency. |
| Route error | Giving concentrated calcium or IV insulin through an unsuitable route | Confirm route, line patency, dilution and monitoring requirements before administration. |
| Timing error | Giving iodide before an antithyroid drug in thyroid storm | Follow the sequence in the specialist protocol and document exact times. |
13. Endocrine drug interactions
| Combination or situation | Potential problem | Action for EMT/student |
|---|---|---|
| Insulin + alcohol or missed meal | Delayed or severe hypoglycaemia | Check glucose, ask about food and observe beyond the first improvement. |
| Insulin + beta-blocker | Beta-blockade may mask tremor and palpitations of hypoglycaemia | Rely on glucose measurement and neuroglycopenic signs, not pulse alone. |
| Levothyroxine + calcium/iron/antacids | Reduced absorption and apparent treatment failure | Ask about timing; refer for dose/spacing advice rather than doubling a dose. |
| Metformin + severe hypoxia/shock/acute kidney injury | Accumulation and lactic acidosis risk | Prioritise resuscitation and urgent clinician review; do not give extra doses. |
| SGLT2 inhibitor + fasting/infection/low-carbohydrate intake | Euglycaemic DKA | Check ketones and acid–base status when symptoms fit, even if glucose is not extreme. |
| Glucocorticoid + insulin or sulfonylurea | Steroid-induced hyperglycaemia; later hypoglycaemia when steroid effect wanes | Trend glucose and communicate the steroid timing. |
| Amiodarone + thyroid disease/levothyroxine | Iodine load and thyroid dysfunction | Include amiodarone history in altered mental status, arrhythmia or thyroid presentations. |
| Warfarin + thyroid replacement changes | Changing thyroid state alters clotting-factor turnover | Check anticoagulant history and communicate recent thyroid medicine changes. |
14. Special populations
- Children: dosing is weight-based, glucose reserves are limited and cerebral injury from rapid osmotic shifts is a concern. Use paediatric protocols and never extrapolate adult doses.
- Pregnancy: glucose targets, insulin needs and thyroid ranges change. Avoid unapproved medicines and seek obstetric/medical advice early.
- Older adults: renal impairment, polypharmacy, frailty and atypical hypoglycaemia make conservative dosing and longer observation important.
- Kidney disease: insulin clearance falls, increasing hypoglycaemia risk; fluid and potassium decisions must be individualised.
- Liver disease: glycogen storage and drug metabolism are impaired; hypoglycaemia may be prolonged.
- Heart failure: fluid resuscitation can precipitate pulmonary oedema; reassess lung sounds, work of breathing and perfusion after every bolus.
- Adrenal insufficiency: vomiting or diarrhoea may make oral therapy ineffective; the emergency injection kit and steroid card are important safety tools.
15. Calculations and monitoring
15.1 Weight-based dose calculation
Required dose = prescribed dose per kilogram × patient weight in kilograms. Write the units at every step. If a 0.1 unit/kg/hour infusion is ordered for a 70 kg adult, the mathematical rate is 7 units/hour; the actual pump preparation and titration must follow the authorised DKA protocol.
For liquid medicines, volume (mL) = dose required ÷ concentration (mg/mL or units/mL). Confirm the concentration on the label before calculating. A second trained person should independently repeat high-alert calculations.
15.2 Monitoring matrix
| Medicine/problem | Baseline checks | During therapy | Stop/escalate indicators |
|---|---|---|---|
| Insulin infusion | Glucose, potassium, renal function, ketones/acid-base status | Hourly glucose in many protocols, potassium and ketones at protocol intervals, fluid balance | Severe hypoglycaemia, falling potassium, worsening shock or unexpected acidosis |
| Hydrocortisone/adrenal crisis | Glucose, sodium, potassium, blood pressure, suspected trigger | Perfusion, glucose, electrolytes, mental status and response to fluids/steroid | Persistent shock, arrhythmia, refractory vomiting or deteriorating consciousness |
| Antithyroid treatment | Clinical severity, ECG, liver history, infection symptoms | Heart rate, temperature, mental status, liver function and blood counts under medical care | Agranulocytosis symptoms, liver failure signs, worsening storm or heart failure |
| Calcium infusion | ECG, calcium, magnesium, renal function and IV access | ECG, symptoms, infusion site and repeat calcium | Extravasation, bradyarrhythmia, hypercalcaemia or persistent tetany |
16. Clinical scenarios for EMT learners
Scenario 1: Awake hypoglycaemia
A 24-year-old with type 1 diabetes is sweaty, trembling and able to swallow. Glucose is 2.6 mmol/L. Give fast-acting oral glucose, reassess after the local interval, then provide longer-acting carbohydrate and investigate missed meals or excess insulin. Do not allow immediate departure solely because the first reading improves.
Scenario 2: Unconscious after sulfonylurea
An older adult is found unconscious with a gliclazide packet nearby. Protect the airway, treat confirmed hypoglycaemia parenterally under protocol, obtain IV access and arrange prolonged observation because recurrent hypoglycaemia may outlast the initial glucose response.
Scenario 3: Euglycaemic DKA
A patient taking dapagliflozin has vomiting, abdominal pain, tachypnoea and glucose of 10.8 mmol/L. The near-normal glucose does not reassure you. Check ketones and acid–base status urgently, provide supportive care and transport for DKA management.
Scenario 4: DKA with potassium concern
A young person has Kussmaul breathing, dehydration and a high glucose. Insulin will lower glucose and shift potassium intracellularly. Do not improvise an insulin bolus; obtain ECG/electrolyte data and follow a controlled protocol with senior oversight.
Scenario 5: Thyroid storm
A febrile patient with known Graves disease has agitation, vomiting, atrial fibrillation and heart failure. Support oxygenation, monitor rhythm, treat hyperthermia and trigger, and seek urgent specialist therapy. A beta-blocker may be dangerous in shock or decompensated failure, so do not treat the heart rate in isolation.
Scenario 6: Adrenal crisis
A patient with chronic prednisolone use has collapse, abdominal pain, hypotension and low glucose after gastroenteritis. Suspect adrenal crisis, give emergency hydrocortisone under protocol without waiting for laboratory confirmation, treat shock and transfer urgently.
Scenario 7: Myxoedema coma
An elderly patient is cold, bradycardic, hypoventilating and confused after pneumonia. Check glucose, support ventilation, warm cautiously, seek hydrocortisone and thyroid replacement guidance, and avoid sedatives that worsen hypoventilation.
17. Documentation and handover
Record the patient’s baseline condition, medicine history, glucose/ketone readings, vital signs, ECG findings, allergies, suspected trigger, treatment, route, dose, batch or concentration where relevant, time given, response, adverse effects and receiving clinician. A concise handover should state:
- Situation: the endocrine emergency suspected and the current threat.
- Background: diabetes type, adrenal/thyroid disease, pregnancy, kidney disease and medication changes.
- Assessment: airway, breathing, circulation, mental status, glucose, ketones, temperature, ECG and perfusion.
- Recommendation: investigations or specialist support required, next glucose/ECG check and concerns about recurrence.
18. Common errors and how to correct them
| Error | Why it is unsafe | Better practice |
|---|---|---|
| Giving oral sugar to an unconscious patient | Aspiration and airway obstruction | Airway protection and parenteral rescue medicine under protocol. |
| Using glucose alone to rule out DKA | Euglycaemic DKA can be missed | Ask about SGLT2 inhibitors and check ketones/acid–base status. |
| Starting insulin before considering potassium | Rapid intracellular shift can cause life-threatening hypokalaemia | Follow the DKA protocol and monitor ECG/electrolytes. |
| Stopping steroids when the patient improves | Adrenal crisis can recur and chronic therapy may have suppressed cortisol production | Continue the prescribed plan and arrange clinician-directed tapering. |
| Giving beta-blocker to every tachycardic thyrotoxic patient | May worsen shock, bronchospasm or decompensated heart failure | Assess perfusion, lung disease and ventricular function; involve senior clinician. |
| Repeating a long-acting insulin dose because glucose remains high | Delayed accumulation and later severe hypoglycaemia | Check timing, ketones, illness and prescribed correction plan. |
19. Quick comparison of endocrine emergencies
| Emergency | Clues | Immediate medicine/support principle | Major danger |
|---|---|---|---|
| Hypoglycaemia | Sweating, tremor, confusion, seizure, low glucose | Oral glucose if safe; IV/IM rescue if not; repeat measurements | Brain injury and recurrence |
| DKA | Polyuria, vomiting, abdominal pain, ketones, Kussmaul breathing | Fluids, controlled insulin and potassium management in hospital protocol | Acidosis, hypokalaemia, cerebral injury and shock |
| HHS | Profound dehydration, very high glucose/osmolality, altered mental status | Careful fluids, electrolyte management and controlled insulin | Thrombosis, seizures, cerebral oedema and cardiovascular collapse |
| Thyroid storm | Fever, agitation, tachyarrhythmia, GI symptoms, heart failure | Supportive care, antithyroid drug, delayed iodide, beta-blockade if safe, steroid | Arrhythmia, pulmonary oedema, shock |
| Myxoedema coma | Hypothermia, bradycardia, hypoventilation, confusion, hyponatraemia | Airway/ventilation, glucose, cautious warming, hydrocortisone and thyroid hormone | Respiratory failure and cardiovascular collapse |
| Adrenal crisis | Hypotension, vomiting, abdominal pain, hypoglycaemia, weakness | Immediate parenteral hydrocortisone, isotonic fluids and glucose when needed | Refractory shock and death |
| Severe hypocalcaemia | Perioral tingling, tetany, seizures, prolonged QT | ECG-monitored calcium replacement under protocol | Laryngospasm and ventricular arrhythmia |
20. Revision questions
- Why is insulin classified as a high-alert medicine?
- Differentiate rapid-acting, short-acting, intermediate-acting and long-acting insulin.
- Why can euglycaemic DKA occur with an SGLT2 inhibitor?
- List five clinical signs of hypoglycaemia and explain why oral fluids are unsafe in an unconscious patient.
- What are the three immediate priorities in a patient with suspected DKA?
- Why must potassium be considered before or during insulin therapy for DKA?
- Compare DKA and HHS in onset, ketones, neurological features and fluid deficit.
- Explain the mechanism and major emergency warning of metformin.
- What is the role of GLP-1 receptor agonists and what adverse effect can complicate emergency care?
- Why can beta-blockers mask hypoglycaemia?
- Describe the sequence and purpose of antithyroid drug, iodide, beta-blocker and steroid therapy in thyroid storm.
- List five features of myxoedema coma.
- Why is hydrocortisone given before or with thyroid hormone when myxoedema coma is suspected?
- State the major signs of adrenal crisis and the first medicine that should not be delayed.
- Explain the difference between glucocorticoid and mineralocorticoid effects.
- Give four medication-history questions that can reveal an endocrine emergency trigger.
- What are the main risks of IV calcium administration?
- How should endocrine medicines be documented during handover?
- Why are children, older adults, pregnant patients and people with kidney disease high-risk groups?
- Write a safe plan for a patient who improves after hypoglycaemia but has taken a long-acting sulfonylurea.
21. Key takeaways
- Endocrine medicines can rapidly alter consciousness, circulation, temperature, electrolytes and cardiac rhythm.
- Glucose measurement is essential, but a normal or modest glucose does not exclude SGLT2-associated DKA.
- Treat hypoglycaemia according to airway safety; oral carbohydrate is for an alert patient who can swallow.
- DKA and HHS require controlled fluids, electrolyte assessment and protocol-driven insulin—not improvised boluses.
- Thyroid storm and myxoedema coma are clinical emergencies: support ABCDE while arranging specialist treatment.
- Suspected adrenal crisis is treated immediately with parenteral hydrocortisone and resuscitation; do not wait for laboratory confirmation.
- Always verify units, concentration, route, timing, renal function, food intake, interactions and the next monitoring time.
- Good documentation and handover prevent recurrence after the patient leaves the emergency scene.
22. Recommended references for further study
- Endocrine Pharmacology – SlideShare teaching resource
- American Diabetes Association, Standards of Care in Diabetes—2026: Pharmacologic Approaches to Glycemic Treatment
- 2024 Consensus Report: Hyperglycemic Crises in Adults With Diabetes
- World Health Organization: Diabetes fact sheet
- American Thyroid Association clinical practice guidelines
- NICE/BNF treatment summary: Adrenal insufficiency
- Society for Endocrinology: Emergency guidance for adrenal crisis
- WHO Electronic Essential Medicines List
Clinical note: This lesson supports EMT learning and examination preparation. It does not replace an authorised prescription, local emergency protocol, senior clinical supervision or the patient’s individual treatment plan. In a deteriorating patient, stabilise ABCDE, call for advanced help and transfer urgently.