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Serum Osmolarity Calculator

Based on the formula:

MeasuredOsm= 2*[Na] + [Glu]/18 +[BUN]/2.8+[EtOH]/4.6+[MeOH]/3.2+[Ethylene Glycol]/6.2

This calculator will estimate the max serum concentration of a single toxic alcohol if that is contributing to an osmolar gap. Please note it is possible for a patient to ingest both ethylene glycol and methanol. Serum estimations in the setting are impossible and a true serum concentration would be needed. Finally, not all elevated osmolar gaps are due to toxic alcohols.