Recognizing factitious hypoglycemia in the family practice setting.

BACKGROUND: Factitious hypoglycemia is a deliberate attempt to induce a low serum glucose level using either insulin or oral hypoglycemic agents. Sulfonylurea-induced hypoglycemia is more common than incidents of insulin abuse, and hypoglycemia caused by these oral agents is biochemically indistinguishable from insulinoma.
METHODS: We describe a case of factitious hypoglycemia resulting from insulin abuse in an adult diabetic patient, review the essentials of glucose homeostasis, and describe diagnostic tests that allow a differential diagnosis. RESULTS AND
CONCLUSION: Factitious hypoglycemia is associated with a higher incidence of suicide, depression, and personality disorders. Insulin-induced hypoglycemia can be detected by an insulin to C-peptide ratio that is greater than 1.0. In the absence of proof to the contrary, insulinoma should be considered the cause of hypoglycemia until another diagnosis is established. The generally poor prognosis for patients with factitious hypoglycemia underscores the importance of early recognition of factitious disorders.