| 🧪 Electrolyte Abnormality | 📌 Causes | 🩺 Clinical Features | 💊 Management | 
 | Hyponatraemia (Low Na⁺) | 
💧 SIADH💊 Diuretics❤️ Heart failure🫁 Liver cirrhosis🧽 Renal disease (nephrotic, CKD) | 
🤢 Nausea, malaise🧠 Confusion, headache⚡ Seizures (severe)Coma if rapid fall | 
🚱 Fluid restriction (SIADH)🔍 Treat cause (e.g. stop thiazide)💉 Hypertonic saline (3%) if severe or seizures — ICU setting⚠️ Correct slowly (<8–10 mmol/L/24h) to avoid osmotic demyelination | 
 | Hypernatraemia (High Na⁺) | 
🚱 Dehydration💧 Diabetes insipidus💉 Hypertonic saline or excess sodium intake | 
😰 Thirst, irritability🧠 Confusion, lethargy⚡ Seizures, coma (severe) | 
💧 Oral/IV hypotonic fluids (e.g. 5% dextrose)⚠️ Correct slowly (≤10 mmol/L/day) → prevent cerebral oedema🔍 Treat cause (DI → desmopressin) | 
 | Hypokalaemia (Low K⁺) | 
💊 Loop/thiazide diuretics🤮 Vomiting, 💩 diarrhoea🧬 Hyperaldosteronism | 
💪 Weakness, cramps📉 Arrhythmias (U waves, long QT)🤢 Constipation, ileus | 
🍌 Oral K⁺ supplements if mild💉 IV potassium (max 10 mmol/hr) if severe/symptomatic🔍 Treat cause, review drugs⚠️ Always recheck Mg²⁺ (hypomagnesaemia worsens hypokalaemia) | 
 | Hyperkalaemia (High K⁺) | 
🧂 Renal failure💊 ACEi/ARB, spironolactone🧬 Addison’s disease | 
💪 Weakness, paraesthesia📉 Arrhythmias (tall peaked T waves, widened QRS) | 
❤️ Calcium gluconate → stabilises myocardium💉 Insulin + glucose infusion (drives K⁺ into cells)💨 Salbutamol nebuliser (temporary shift)🧴 Sodium bicarbonate if acidosis🩸 Dialysis if severe/refractory | 
 | Hypocalcaemia (Low Ca²⁺) | 
⬇️ Hypoparathyroidism☀️ Vitamin D deficiency🧽 CKD (secondary hyperparathyroidism) | 
🤲 Tetany, carpopedal spasm⚡ Seizures🔔 Chvostek’s & Trousseau’s signs | 
💊 Oral calcium + Vit D (mild)💉 IV calcium gluconate (symptomatic/severe)🔍 Correct Mg²⁺ if low | 
 | Hypercalcaemia (High Ca²⁺) | 
🦴 Primary hyperparathyroidism🎗️ Malignancy (bone mets, PTHrP)💊 Thiazides, lithium | 
“Stones, bones, groans, psychiatric overtones”🧠 Confusion, fatigue🚽 Polyuria, polydipsia, dehydration | 
💧 IV saline rehydration (first-line)💊 Bisphosphonates (e.g. zoledronic acid)💊 Calcitonin (short-term)🔍 Treat cause (e.g. resect parathyroid adenoma) |