Osmolal Gap (Serum)

Na

mmol/L

Urea

mmol/L

Glucose

mmol/L

Ethanol

mmol/L

Measured Osmolality

mosm/kg

Calc. Osmolality

mosm/kg

Osmolal Gap

mosm/kg

Formula

Osm. gap = meas. osm. - calc. osm.
Calc. osm. = 2*Na + Urea + Glucose + Ethanol (optional)

Info

References:
Gennari FJ. N Engl J Med. 1984 Jan 12;310(2):102-5. -> PubMed