Table of ContentsView AllTable of ContentsSigns and SymptomsCausesDiagnosisTreatmentPrevention
Table of ContentsView All
View All
Table of Contents
Signs and Symptoms
Causes
Diagnosis
Treatment
Prevention
Reactive hypoglycemia, also calledpostprandial hypoglycemia, occurs when your blood sugar (blood glucose) drops after eating. This “sugar crash” usually occurs within a few hours of eating. Why it happens is still under study, but it typically resolves quickly with a small amount of food or drink, like orange juice, or with glucose gel.
People who don’t have diabetes experience reactivehypoglycemia, but they may be more at risk of developing diabetes if factors like a family history are present.It can occur after bariatric (weight loss) surgery or, rarely, due toinsulinoma(endocrine tumor).Sometimes, though, an episode of reactive hypoglycemia can occur with diabetes due to exercise levels, or when too much insulin is taken before a meal.
Symptoms and Signs
Hypoglycemia is the medical term for low blood sugar, with symptoms that typically occur when glucose levels drop below 70 milligrams per deciliter of blood (mg/dL).
Commonsymptoms of reactive hypoglycemiainclude:
Reactive hypoglycemia occurs after a meal. Its causes are different from hypoglycemia that occurs due to fasting for long periods without food, or in most situations where people diagnosed with diabetes are working to manage their blood sugar levels.
The symptoms of reactive hypoglycemia are rarely life-threatening but may be a sign of an underlying medical condition such asAddison’s disease.If severe symptoms occur, seek immediate medical care.
When to See a Healthcare ProviderIf the drop in blood sugar is severe, seek immediate care if you are unable to reverse symptoms with glucose gel or a rapid-acting food or drink. Severe symptoms of reactive hypoglycemia include:Pale skin (pallor)Feeling sleepy, weak, or clumsyBlurry or double-visionTingling or numbness in the lips, tongue, or cheeksHeadachesSleep disturbances, like nightmares or crying outSeizuresYou also should notify your healthcare provider if you are having reactive hypoglycemia episodes more often, even if your symptoms are not severe or life-threatening.
When to See a Healthcare Provider
If the drop in blood sugar is severe, seek immediate care if you are unable to reverse symptoms with glucose gel or a rapid-acting food or drink. Severe symptoms of reactive hypoglycemia include:Pale skin (pallor)Feeling sleepy, weak, or clumsyBlurry or double-visionTingling or numbness in the lips, tongue, or cheeksHeadachesSleep disturbances, like nightmares or crying outSeizuresYou also should notify your healthcare provider if you are having reactive hypoglycemia episodes more often, even if your symptoms are not severe or life-threatening.
If the drop in blood sugar is severe, seek immediate care if you are unable to reverse symptoms with glucose gel or a rapid-acting food or drink. Severe symptoms of reactive hypoglycemia include:
You also should notify your healthcare provider if you are having reactive hypoglycemia episodes more often, even if your symptoms are not severe or life-threatening.
Triggers for reactive hypoglycemia can include eating high-carbohydrate meals or snacks.One theory as to why it occurs is that when a person eats carbs with a high glycemic index, the body produces enough insulin to combathyperglycemia.
Health conditions other than diabetes that are known to cause reactive hypoglycemia can include:
Too much insulin intake can cause lower levels of glucose in the blood.
Reactive hypoglycemia can be diagnosed using an oral glucose tolerance test (OGTT) or amixed meal tolerance test (MMTT).
The healthcare provider will look for results, often called the Whipple’s Triad, that include:
Results from tests used todiagnose hypoglycemiaalso can help your healthcare provider to rule out other possible causes of the symptoms, including mental health concerns likeanxiety.
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. However, if the symptoms are recurring, they may be the result of an underlying condition that needs treatment.
If you have an episode of reactive hypoglycemia, you can use food to help restore normal blood sugar levels.
This is accomplished with the “15-15 Rule,” which involves eating 15 grams offast-acting carbohydratesand checking your blood sugar 15 minutes later to see if the levels have normalized. The American Diabetic Association recommends:
Once your symptoms have eased, have a snack if your next meal is more than an hour away to prevent your blood sugar from dropping again.
For an underlying medical condition, the treatment will focus on resolving or managing the condition. This may include the surgical removal of an insulinoma or, in the case of NIPHS, the partial removal of the pancreas.
Certain dietary and lifestyle changes may reduce the odds of a reactive hypoglycemia episode, even where the cause is not yet known. You can try:
Talk to your healthcare provider about your symptoms and lifestyle changes, as it’s possible that medication or other measures may be needed, too.
Summary
Reactive hypoglycemia is a drop in blood glucose (sugar) that occurs after eating. Symptoms usually develop within a few hours of consuming food and may include shakiness, dizziness, nausea, rapid heartbeat, and sweating. 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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