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Trouble-Shooting High Blood Glucose Levels (for people with Type 1 Diabetes)

2024/09/27

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Your blood glucose levels may go high despite your best efforts. This can be an occasional occurrence. Or it can be a repeated pattern day after day.

 

While you can use the Insulin Sensitivity Factor (ISF) to temporarily correct high readings, identifying and addressing the underlying causes is crucial. 

POTENTIAL CAUSES OF HYPERGLYCAEMIA:

1. Decreased insulin sensitivity  
Possible reasons include illness*, reduced physical activity, pre-menstrual hormonal changes or new medications such as traditional medications or steroids. 

*It is important to formulate an individualized sick day management plan with your healthcare team. If you feel unwell with blood glucose levels persistently over 14 mmol/L, refer to your plan. 


 2. Missed or delayed insulin doses (For example, administering quick-acting insulin post-meal instead of pre-meal, or delaying basal insulin injections)  


3. Insufficient basal insulin doses 

4. Insufficient quick-acting insulin for meal carbohydrates  
This may be due to an incorrect insulin-to-carbohydrate ratio (ICR) or underestimating carbohydrate content in meals. 

5. Injecting insulin into lumpy or lipohypertrophic sites 


6. Expired or spoilt insulin (For example, insulin exposed to high temperatures, like in a car under the sun, may become ineffective.)  

OPTIMISING PRE-BREAKFAST GLUCOSE READINGS

Starting the day with a favourable pre-breakfast glucose level can positively influence the rest of your day.  

If you consistently have high glucose readings upon waking, consider exploring the following reasons with your healthcare team: 

 

  • High bedtime glucose levels (post-dinner readings): This may be due to insufficient quick-acting insulin for dinner, excessive carbohydrate intake or a high-fat dinner.

 

  • Supper: Depending on the carbohydrate content of your supper, you might need quick-acting insulin. Consult your healthcare team for management strategies.

 

  • Nocturnal hypoglycaemia: Leading to rebound hyperglycaemia in the morning

 

  • Insufficient basal insulin

 

  • Dawn phenomenon 
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