Care at NUH

Hypoglycemia and Type 1 Diabetes


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Hypoglycaemia occurs when blood sugar levels fall below 4.0 mmol/L. Symptoms may vary, but common early signs include hunger, sweating, hand tremors, anxiety and a rapid heartbeat. Prompt treatment of hypoglycaemia is crucial, as it can become dangerous if left untreated. 


Follow the appropriate steps to raise your blood sugar level quickly. Log all blood glucose readings and events to discuss with your healthcare team. Always identify potential causes or triggers for hypoglycaemia. 


Severe hypoglycaemia occurs when the blood glucose levels drop so low that you become incapable of self-treatment. Symptoms can include confusion, seizures and loss of consciousness. 

In such cases, have someone call 995 immediately for medical assistance and an intravenous glucose infusion. 

If your family is trained, they can administer an emergency glucagon injection to elevate your blood sugar. Discuss keeping a glucagon kit at home with your healthcare team.  

Recurrent hypoglycaemia can lead to impaired awareness of hypoglycaemia, where warning symptoms are diminished or absent, increasing the risk of severe hypoglycaemia. If you suspect you have this condition, discuss your symptoms and concerns with your healthcare team. Avoid driving, operating heavy machinery or engaging in high-risk activities such as rock-climbing or diving. Regaining awareness is possible with professional guidance. 

Understanding the causes of hypoglycaemia is key to reducing its incidence. Common causes include: 

Meal-related issues: 

Delaying/skipping meals after insulin administration or insufficient carbohydrates for the administered insulin 

Insulin-related factors: 

Excessive basal or correction insulin  

Exercise-related factors: 

Prolonged or intense physical activity or increased insulin sensitivity post-exercise (typically aerobic exercises such as running, walking, swimming, cycling) 

Other factors: 

Weight loss, alcohol consumption or rare medical conditions such as hypoadrenalism 


Episodes of hypoglycaemia can be reduced without compromising overall glycaemic control with the following strategies. Many of these strategies are covered in the  online resource page for Type 1 Diabetes. 

1. Smart insulin usage 

  • Correct basal insulin dosing 
  • Appropriate quick-acting insulin dosing for meals 
  • Safe correction of high blood glucose levels  

2. Proper glucose management before, during and after physical activity 

3. Utilisation of flash glucose monitoring (FGM) or continuous glucose monitoring sensor (CGMS), particularly those with impaired awareness or frequent hypoglycaemia. Real-time CGMS can alert you to low or dropping glucose levels.  

4. Your healthcare team might recommend an insulin pump for frequent hypoglycaemia.

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