Reactive hypoglycemia happens when your blood sugar (blood glucose) drops to abnormally low levels after you eat.
This “sugar crash” usually occurs within a few hours of eating.
It is also calledpostprandial hypoglycemia.
Illustration by Alex Dos Diaz for Verywell Health
Reactivehypoglycemiacan occur in people with or without diabetes.
Common symptoms of reactive hypoglycemia include:
Reactive hypoglycemia occurs after a meal.
Causes
Reactive hypoglycemia can occur in people with or without diabetes.
The OGTT includes only glucose.
Glucose and insulin levels are then assessed.
Treatment
Treatment for reactive hypoglycemia will depend on the cause.
In many cases, blood sugar can be corrected quickly and people don’t need medical treatment.
Sometimes, medication is prescribed to help treat reactive hypoglycemia.
These medications may delay the digestion of carbohydrates or reduce insulin secretion.
For an underlying medical condition, the treatment will focus on resolving or managing the condition.
Summary
Reactive hypoglycemia is a drop in blood glucose (sugar) that occurs after eating.
Severe cases can lead to fainting or seizures.
Reactive hypoglycemia can occur for other reasons beyond diabetes.
The treatment typically involves eating fast-acting carbohydrates that can quickly bring blood sugar levels back to normal.
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