Thiamine As Adjunctive Therapy for Diabetic Ketoacidosis

Inclusion Criteria: * Bicarbonate ≤15 mEq/L * Anion gap \> 12 mEq/L * Blood pH≤ 7.24 (if already obtained by clinical team) * Urine ketones (qualitative) or serum ketones (β-hydroxybutyric acid) \> 3 mmol/L * Enrollment within 6 hours of presentation Exclusion Criteria: * Current thiamine supplementation ≥ 6 milligrams per day (i.e., more than a multivitamin) * Competing causes of severe acidosis including seizure, carbon monoxide poisoning, cyanide toxicity, cardiac arrest, liver dysfunction (specifically defined as known cirrhosis) * Known allergy to thiamine * Competing indication for thiamine administration as judged by the clinical team (e.g., significant alcohol use) * Research-protected populations (pregnant women and prisoners) * Patient enrolled previously in same study * Code status of Do Not Resuscitate/Do Not Intubate (DNR/DNI) or Comfort Measures Only (CMO)