I think I have reactive hypoglycemia. What can I do for my symptoms?
Answer From M. Regina Castro, M.D.
Reactive hypoglycemia (postprandial hypoglycemia) refers to low blood sugar that occurs after a meal — usually within four hours after eating. This is different from low blood sugar (hypoglycemia) that occurs while fasting.
Signs and symptoms of hypoglycemia may include:
- Hunger
- Pale skin
- Weakness
- Shakiness
- Sweating
- Lightheadedness
- Anxiety
- Confusion
If you use insulin or other blood sugar lowering medications to treat diabetes, hypoglycemia after eating may mean that your medication dose needs to be adjusted.
For most people with reactive hypoglycemia, the actual cause isn't clear. But, the symptoms of this condition may relate to what food was eaten or variations in the timing of the food moving through the digestive system. Other possible causes of reactive hypoglycemia include alcohol, certain surgical procedures (gastric bypass or surgery for an ulcer), inherited metabolic disorders and some tumors.
Generally, a medical evaluation is done to learn if symptoms are caused by low blood sugar and if so, whether symptoms get better when blood sugar returns to normal. Additional testing may need to be done if you have more-serious symptoms.
Reactive hypoglycemia usually doesn't require medical treatment. However, any underlying medical condition will need to be treated. Dietary changes often help lessen your symptoms. Try making changes to the timing and composition of your meals, such as:
- Eating a balanced diet, including lean and nonmeat sources of protein, and high-fiber foods, including whole grains, fruits and vegetables
- Avoiding sugary foods and processed simple carbohydrates, such as white bread or white pasta, especially on an empty stomach
- Eating food when drinking alcohol, if you drink
- Eating several small meals and snacks throughout the day, about three hours apart during waking hours
With
M. Regina Castro, M.D.
May 26, 2021
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