Mnemonic

Electrolyte Reference Ranges

A memory aid for the normal ranges of common biochemistry results.

Expansion

The standard adult reference values for the basic metabolic panel

Expansion

Test Typical adult range
Sodium 135 to 145 mmol/l
Potassium 3.5 to 5.0 mmol/l
Chloride 95 to 105 mmol/l
Bicarbonate 22 to 28 mmol/l
Urea 2.5 to 7.0 mmol/l
Creatinine 60 to 110 micromol/l
Glucose (fasting) 3.5 to 5.5 mmol/l
Corrected calcium 2.20 to 2.60 mmol/l
Phosphate 0.8 to 1.5 mmol/l
Magnesium 0.7 to 1.0 mmol/l
Albumin 35 to 50 g/l
Osmolality 275 to 295 mOsm/kg

Calcium correction: add 0.02 mmol/l to the measured calcium for every 1 g/l that albumin falls below 40. This matters because about half of plasma calcium is albumin-bound and only the ionised fraction is active.

Ranges vary between laboratories and with age, pregnancy and ethnicity, so the reporting laboratory’s own values should be used. Paediatric ranges differ substantially, particularly for alkaline phosphatase, which is high during growth, and for creatinine, which reflects muscle mass.