Diagnostics

• Confirm low blood glucose (via fingerstick or BMP) and check for Whipple triad.

• Investigate any acute illness as a cause (e.g., infection, sepsis, burns).

• Review medications

• Perform diagnostic workup based on the leading differential diagnosis and whether the patient has diabetes.

Further workup for hypoglycemia is usually only indicated if all features of the Whipple triad are present.

Do not delay treatment of symptomatic hypoglycemia in favor of formally testing for blood glucose levels.

• Hypoglycemia in diabetic patients is almost always due to acute illness and/or medications (e.g., insulin) and further workup is generally not indicated.

• Initial workup if no obvious trigger is identified:

  • Routine laboratory studies: CBC, BMP, liver chemistries

  • Septic workup as directed by clinical suspicion: e.g., CXR, urinalysis, blood cultures

  • Consider sulfonylurea and exogenous insulin levels.

• Rule out critical illness and drugs that cause hypoglycemia.

• Consider other causes of hypoglycemia in nondiabetic patients, e.g., recent gastric bypass surgery.

• In seemingly well patients with no obvious cause of hypoglycemia, assess for insulinoma.

  • Obtain initial studies, including insulin, C-peptide, proinsulin, and anti-insulin receptor autoantibodies.

  • Consider a glucagon tolerance test and 72-hour fasting test to support the diagnosis.

  • See “Diagnostics for insulinoma” for details on diagnostic workup for endogenous hyperinsulinism.

Nonsuppressed serum insulin concentrations with decreased serum C-peptide and proinsulin concentrations are consistent with exogenous insulin use.

• Primary CNS: stroke, TIA, seizure disorder, tumor, cerebral edema, TBI, dementia

• Psychiatric: depression, anxiety, psychosis, delirium

• Metabolic/autoregulatory: hypoxia, endocrine derangements, electrolyte abnormalities, shock

• Infectious: sepsis, meningitis, encephalitis

• Pharmacological or toxin-related

  • Medication side effects

  • Substance intoxication

  • Withdrawal (see “Overview of substance intoxication and withdrawal”)

  • Poisoning

• Cardiac: arrhythmia, ischemia

• Pulmonary: pulmonary embolism, pneumothorax

• Psychiatric: panic disorder

• Metabolic/autoregulatory: hyperthyroidism, thyroid storm, dehydration, shock

• Infectious: active infection, sepsis

• Pharmacological or toxin-related: cocaine, amphetamine, alcohol intoxication, or withdrawal

• Pain

Monitor patients regularly for rebound hypoglycemia after treatment.

• Alert and oriented patients

  • Oral glucose 15–20 g [14]

  • Fast-acting carbohydrates (e.g., glucose tablets, candy, or fruit juice) [14]

• Patients with altered mental status (or impaired oral intake) [5]

  • IV dextrose (e.g., D50W): Repeat after 15 minutes if hypoglycemia persists; multiple doses may be required. [11][14]

    • Adults: 50% dextrose DOSAGE

    • Children (excluding neonates): 10% dextrose DOSAGE OR 25% dextrose DOSAGE [18][19]

  • IM glucagonDOSAGE: if neither oral nor IV routes of administering glucose are feasible [14]

For patients with type 1 diabetes presenting with hypoglycemia and using insulin pumps, do not discontinue insulin pumps and treat hypoglycemia as usual. Removing the insulin pump puts patients at risk for diabetic ketoacidosis. [11]

Avoid giving orange juice to patients with CKD on a low-potassium diet as it is high in potassium. [14]

• Chronic alcohol dependence and/or malnourishment: Consider IV thiamine. [

• Sulfonylurea toxicity: consider administering octreotide under the guidance of endocrinology to inhibit endogenous insulin release