Editing Hypoglycemia (section)

==Diagnosis==
The most reliable method of identifying hypoglycemia is through identifying [[Whipple's triad]].<ref name="Jameson_2018" /><ref name="Cry2009" /> The components of [[Whipple's triad]] are a blood sugar level below 70&nbsp;mg/dL (3.9&nbsp;mmol/L), symptoms related to low blood sugar, and improvement of symptoms when blood sugar is restored to normal.<ref name="Jameson_2018" /><ref name="Cry2009" /> Identifying [[Whipple's triad]] in a patient helps to avoid unnecessary [[Medical test|diagnostic testing]] and decreases [[Health care prices in the United States|healthcare costs]].<ref name="Cry2009" />

In those with a history of diabetes treated with [[Insulin (medication)|insulin]], [[Meglitinide|glinides]], or [[sulfonylurea]], who demonstrate Whipple's triad, it is reasonable to assume the cause of hypoglycemia is due to insulin, glinides, or sulfonylurea use.<ref name="Cry2009" /> In those without a history of diabetes with hypoglycemia, further diagnostic testing is necessary to identify the cause.<ref name="Cry2009" /> Testing, during an episode of hypoglycemia, should include the following:
* [[Blood sugar level|Plasma glucose]] level, not [[Point of care|point-of-care]] measurement<ref name="Jameson_2018" /><ref name="Cry2009" />
* Insulin level<ref name="Jameson_2018" /><ref name="Cry2009" />
* [[C-peptide]] level<ref name="Jameson_2018" /><ref name="Cry2009" />
* [[Proinsulin]] level<ref name="Jameson_2018" /><ref name="Cry2009" />
* [[Beta-Hydroxybutyric acid|Beta-hydroxybutyrate]] level<ref name="Jameson_2018" /><ref name="Cry2009" />
* Oral hypoglycemic agent screen<ref name="Cry2009" />
* Response of blood glucose level to glucagon<ref name="Cry2009" />
* Insulin [[Antibody|antibodies]]<ref name="Cry2009" />
If necessary, a diagnostic hypoglycemic episode can be produced in an inpatient or outpatient setting.<ref name="Jameson_2018" /> This is called a diagnostic [[Fasting|fast]], in which a patient undergoes an observed fast to cause a hypoglycemic episode, allowing for appropriate blood work to be drawn.<ref name="Jameson_2018" /> In some, the hypoglycemic episode may be reproduced simply after a mixed meal, whereas in others a fast may last up to 72 hours.<ref name="Jameson_2018" /><ref name="Cry2009" />

In those with a suspected [[insulinoma]], imaging is the most reliable diagnostic technique, including [[ultrasound]], [[CT scan|computed tomography (CT)]] imaging, and [[magnetic resonance imaging|magnetic resonance imaging (MRI)]].<ref name="Jameson_2018" /><ref name="Cry2009" />
=== Differential diagnosis ===
Other conditions that may present at the same time as hypoglycemia include the following:
* Alcohol or [[Substance intoxication|drug intoxication]]<ref name="Cry2009" /><ref name=":3">{{Cite web |title=Hypoglycemia in adults without diabetes mellitus: Clinical manifestations, diagnosis, and causes |url=https://www.uptodate.com/contents/hypoglycemia-in-adults-without-diabetes-mellitus-clinical-manifestations-diagnosis-and-causes |url-status=live |archive-url=https://web.archive.org/web/20220126212612/https://www.uptodate.com/contents/hypoglycemia-in-adults-without-diabetes-mellitus-clinical-manifestations-diagnosis-and-causes?sectionName=DIFFERENTIAL+DIAGNOSIS&search=hypoglycemia+differential&topicRef=1798&anchor=H18546202&source=see_link#H18546202 |archive-date=26 January 2022 |access-date=14 January 2022 |website=www.uptodate.com |vauthors=Vella A}}</ref>
* [[Arrhythmia|Cardiac arrhythmia]]<ref name="Cry2009" /><ref name=":3" />
* [[Valvular heart disease]]<ref name="Cry2009" /><ref name=":3" />
* Postprandial syndrome<ref name=":3" />
* [[Hyperthyroidism]]<ref name=":3" />
* [[Pheochromocytoma]]<ref name=":3" />
* Post-gastric bypass hypoglycemia<ref name="Cry2009" /><ref name=":3" />
* [[Generalized anxiety disorder]]<ref name=":3" />
* Surreptitious insulin use<ref name="Cry2009" /><ref name=":3" />
* Lab or blood draw error (lack of antiglycolytic agent in collection tube or during processing)<ref>{{Cite web |title=Low Blood Glucose (Hypoglycemia) - NIDDK |url=https://www.niddk.nih.gov/health-information/diabetes/overview/preventing-problems/low-blood-glucose-hypoglycemia |access-date=2024-08-16 |website=National Institute of Diabetes and Digestive and Kidney Diseases |language=en-US}}</ref><ref name=":3" />