What causes hypoglycemia (low blood sugar) after eating?

From the Guidelines

Hypoglycemia after eating should be managed through dietary modifications, focusing on the type and quantity of carbohydrates consumed, as this primarily determines postprandial glucose levels. According to the American Diabetes Association's position statement 1, the rate of appearance of glucose in the bloodstream and its clearance from the circulation are key factors in maintaining blood glucose levels within a narrow range after a meal.

Key Considerations

• The quantity and type of carbohydrates in foods influence postprandial glucose levels, with simple sugars and refined carbohydrates potentially causing sharper fluctuations in blood sugar.
• Eating smaller, more frequent meals that include protein, healthy fats, and complex carbohydrates can help prevent hypoglycemia after eating.
• Foods with a low glycemic index, such as whole grains, legumes, and non-starchy vegetables, are recommended as they cause a more gradual increase in blood glucose levels.

Management Strategies

• Limiting or avoiding alcohol and caffeine is advisable as they can exacerbate symptoms of hypoglycemia.
• If dietary changes are insufficient to manage symptoms, consulting a healthcare provider for further evaluation and potential medication, such as acarbose, may be necessary.
• Keeping a food diary can help identify specific foods or patterns that trigger hypoglycemic episodes, allowing for more targeted dietary adjustments.

Underlying Causes

• Reactive hypoglycemia can occur due to an exaggerated insulin response after consuming carbohydrates, and it may be associated with early diabetes, certain types of gastric surgery, or as an idiopathic condition.
• Symptoms of reactive hypoglycemia typically include shakiness, sweating, dizziness, hunger, and confusion, usually appearing 1-3 hours after eating.

From the FDA Drug Label

OVERDOSAGE Hypoglycemia may occur as a result of an excess of insulin relative to food intake, energy expenditure, or both. Because acarbose given in combination with a sulfonylurea or insulin will cause a further lowering of blood glucose, it may increase the potential for hypoglycemia Sulfonylurea agents or insulin may cause hypoglycemia. Acarbose tablets itself do not cause hypoglycemia even when administered to patients in the fasted state.

Hypoglycemia after eating can occur due to an excess of insulin relative to food intake or energy expenditure. Additionally, when acarbose is given in combination with sulfonylurea or insulin, it may increase the potential for hypoglycemia. However, acarbose itself does not cause hypoglycemia when administered to patients in the fasted state or after eating. Key points to consider:

• Insulin and sulfonylurea can cause hypoglycemia after eating.
• Acarbose can increase the potential for hypoglycemia when given in combination with insulin or sulfonylurea.
• Acarbose itself does not cause hypoglycemia after eating. 2 3 3

From the Research

Hypoglycemia after Eating

• Hypoglycemia, or low blood sugar, can occur after eating in individuals with diabetes, particularly those taking certain medications such as sulfonylureas and meglitinides 4, 5, 6.
• Sulfonylureas, a class of oral hypoglycemic drugs, can increase insulin secretion, but may also induce hyperinsulinemia and prolonged hypoglycemia 4.
• Meglitinide analogues, another class of oral hypoglycemic agents, increase insulin secretion, particularly during the early phase of insulin release, and may be associated with hypoglycemia 7.
• Certain antibiotics, such as cefditoren, tigecycline, ertapenem, and clarithromycin, may also be associated with hypoglycemia, especially when taken with sulfonylureas or meglitinides 8.

Mechanisms and Characteristics

• Sulfonylureas and glinides stimulate the release of insulin from pancreatic cells and have extrapanular hypoglycemic effects, such as reducing the clearance rate of insulin in the liver and enhancing the sensitivity of peripheral tissues to insulin 5.
• Meglitinide analogues, such as repaglinide and nateglinide, increase insulin secretion and may be effective in reducing glycosylated haemoglobin levels in individuals with type 2 diabetes mellitus 7.

Risk Factors and Side Effects

• The risk of hypoglycemia is increased in individuals taking sulfonylureas and meglitinides, particularly in those with renal or hepatic impairment, or those taking other medications that may interact with these drugs 4, 5, 6.
• Weight gain and diarrhea are common side effects of meglitinide analogues, while hypoglycemia is a rare but potentially severe side effect 7.