Episodes suggesting hypoglycaemia in a non-diabetic adult

During an episode (at the laboratory or in the emergency department)

• Venous plasma glucose, taken during symptoms
• Venous sample in a fluoride tube (fluoride-oxalate), sent without delay; capillary blood glucose is not enough.
• Note the time of the last meal and the time of the episode; report whether symptoms resolve after sugar intake.

Depending on the context

• 8 am serum cortisol (if signs of adrenal insufficiency)if neededClinical suspicion of adrenal insufficiency: cortisol deficiency is among the causes of hypoglycaemia to look for; the SFE asks to rule out primary adrenal insufficiency (baseline cortisol and ACTH) before any other investigation ^[2,3,4]. See the page “Adrenal insufficiency”.
• Serum creatinine with eGFRif needednon-French guidelineOlder, malnourished patient, with known renal, hepatic or heart failure, or on multiple medicines: organ failure and malnutrition are causes of hypoglycaemia in the “sick” patient ^[3].
• ASTif needednon-French guidelineOlder, malnourished patient, with known renal, hepatic or heart failure, or on multiple medicines: organ failure and malnutrition are causes of hypoglycaemia in the “sick” patient ^[3].
• ALTif needednon-French guidelineOlder, malnourished patient, with known renal, hepatic or heart failure, or on multiple medicines: organ failure and malnutrition are causes of hypoglycaemia in the “sick” patient ^[3].

• Endocrinology opinion. The aetiological tests are taken during the hypoglycaemia (spontaneous or provoked by a 72-hour fasting test as an inpatient): venous plasma glucose, insulin, C-peptide, proinsulin, β-hydroxybutyrate, screen for sulfonylureas, anti-insulin antibodies.
• Severe episode (altered consciousness, seizure): give sugar and send to the emergency department.

During an episode (2 to 4 hours after a meal)

• Venous plasma glucose, taken during symptoms
• Venous sample in a fluoride tube (fluoride-oxalate), sent without delay. Note the time of the meal and the time of the episode.

Depending on the context

• 8 am serum cortisol (if signs of adrenal insufficiency)if neededClinical suspicion of adrenal insufficiency after bariatric surgery: the Gulf countries consensus (2026) then asks to look for cortisol deficiency, and the 2024 British recommendation lists hypocortisolism among the causes to rule out ^[9,10]; the SFE asks for it in hypoglycaemia in general, with no provision specific to bariatric surgery ^[4]. See the page “Adrenal insufficiency”.