What is the correct medical term for reactive hypoglycemia?

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Correct Medical Terminology for Reactive Hypoglycemia

The correct medical term for reactive hypoglycemia is "postprandial reactive hypoglycemia" (PRH), which refers to hypoglycemia occurring 2-5 hours after food intake. 1, 2

Terminology and Classification

  • Postprandial reactive hypoglycemia (PRH) is the preferred and most accurate medical term, emphasizing the temporal relationship to meals 1, 2

  • The term "reactive hypoglycemia" itself remains acceptable and widely used in clinical practice, distinguishing it from fasting hypoglycemia 3

  • The outdated term "functional hypoglycemia" should be avoided as it contributes vagueness and lacks diagnostic precision 3

Clinical Subtypes of Reactive Hypoglycemia

PRH manifests in three distinct temporal patterns 1:

  • Idiopathic reactive hypoglycemia: occurs at 180 minutes (3 hours) post-meal 1
  • Alimentary reactive hypoglycemia: occurs within 120 minutes (2 hours), typically seen after gastrointestinal surgery 1, 3
  • Late reactive hypoglycemia: occurs at 240-300 minutes (4-5 hours), associated with insulin resistance and may predict future diabetes 1

Diagnostic Criteria

  • True reactive hypoglycemia requires documented plasma glucose <55-60 mg/dL (<3.0-3.3 mmol/L) occurring simultaneously with sympathetic or neuroglycopenic symptoms 1, 2, 4

  • This corresponds to Level 2 hypoglycemia in the American Diabetes Association classification system, defined as glucose <54 mg/dL (<3.0 mmol/L) 5

  • Symptoms must resolve with glucose administration or food intake to confirm the diagnosis 6, 2

Important Clinical Caveat

A low glucose value during an oral glucose tolerance test (OGTT) alone is NOT sufficient to diagnose reactive hypoglycemia due to high false-positive rates 2, 4. The diagnosis requires documentation of hypoglycemia during spontaneous symptomatic episodes in the patient's natural environment 6, 3.

References

Research

Postprandial Reactive Hypoglycemia.

Sisli Etfal Hastanesi tip bulteni, 2019

Research

Postprandial reactive hypoglycemia.

Diabetes & metabolism, 2000

Research

Reactive hypoglycemia.

Endocrinology and metabolism clinics of North America, 1989

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Evaluation and Management of Non-Diabetic Hypoglycemia with Neuroglycopenic Symptoms

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2026

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Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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