Immediate Basal Rate Reduction for Nocturnal Hypoglycemia
You need to reduce your overnight basal rate immediately by 10-20% (from 1.0 unit/hour to 0.8-0.9 units/hour) and monitor for at least 3 consecutive nights before making further adjustments. 1
Understanding Your Current Situation
Your blood glucose dropping to the 30s overnight represents severe nocturnal hypoglycemia that requires urgent intervention. With a current basal rate of 1 unit/hour (24 units/day basal), you need to assess whether you're experiencing overbasalization - a common cause of nocturnal hypoglycemia. 1
Key Assessment Points
Check your total daily insulin dose (TDD): Your basal insulin should represent only 40-60% of your TDD. If your 24-unit basal dose exceeds 50-60% of your total daily insulin (basal + boluses), this indicates overbasalization and significantly increases nocturnal hypoglycemia risk. 1, 2
Calculate from your pump menu: Review your 24-hour basal total and compare it to your complete daily insulin usage including all meal and correction boluses. 1
Immediate Adjustment Protocol
Step 1: Reduce Overnight Basal Rate
Decrease your basal rate by 10-20% during the hours when hypoglycemia occurs (typically midnight to 6 AM). This means reducing from 1.0 unit/hour to 0.8-0.9 units/hour for those specific hours. 1, 3
Do not wait for multiple episodes before making this change - recurrent hypoglycemia leads to hypoglycemia unawareness and impaired counterregulatory responses, making future episodes more dangerous. 1
Step 2: Monitor Pattern Over 3 Nights
Adjust basal rates based on patterns, not isolated readings. You must monitor fasting blood glucose for at least 3 consecutive nights before making additional changes. 1
The American Diabetes Association specifically recommends adjusting basal insulin every 3 days based on documented patterns. 1
Step 3: Consider Temporary Basal Reduction
If you engaged in intense physical activity during the day, use your pump's temporary basal rate feature to reduce overnight insulin delivery by 10-50% on those specific nights. 1
Advanced Technology Solutions
Sensor-Augmented Pump with Threshold Suspend
If nocturnal hypoglycemia persists despite basal rate adjustments, you should strongly consider upgrading to sensor-augmented pump therapy with automatic low glucose suspend. 1 This technology has been proven to:
- Reduce nocturnal hypoglycemia by 31.8% without increasing HbA1c values 4
- Prevent hypoglycemia in 75% of nights (84% of individual events) when it would otherwise occur 5
- Decrease the area under the curve for nocturnal hypoglycemic events by 37.5% 4
The threshold-suspend feature automatically stops insulin delivery at a preset glucose value, then resumes when levels recover. 6, 4
Continuous Glucose Monitoring Benefits
Real-time CGM with alarms significantly improves detection of nocturnal hypoglycemia, which is underestimated 40-60% of the time with fingerstick monitoring alone. 1, 7 Automated insulin delivery (AID) systems have their particular strength in nocturnal glucose regulation. 1, 7
Critical Safety Considerations
What NOT to Do
Do not adjust your insulin sensitivity factor (ISF of 50) based on nocturnal hypoglycemia - your ISF addresses pre-meal hyperglycemia and should only be changed if correction doses consistently fail to bring glucose into target range during waking hours. 1
Avoid "stacking" correction doses in the evening - while your pump's insulin-on-board calculator should prevent this, manual overrides can lead to nocturnal hypoglycemia. 1
Do not adjust your carbohydrate ratio based on overnight lows - this ratio determines mealtime insulin coverage and should only be adjusted if post-meal glucose readings are consistently out of target. 1
Immediate Treatment Protocol
When you experience hypoglycemia in the 30s:
- Consume 15-20 grams of glucose immediately using glucose tablets or carbohydrate-containing foods/beverages. 1
- Recheck blood glucose 15-20 minutes after treatment. If levels remain low, repeat the glucose dose. 1
- Document every episode in your pump or logbook to identify patterns for regimen optimization. 1
Behavioral Prevention Strategies
Consume a source of carbohydrates at bedtime to reduce overnight hypoglycemia risk, with moderate amounts helping maintain stable glucose levels. 1
If you consume alcohol, always take it with food - alcohol increases hypoglycemia risk in patients on insulin. 1
Adjust timing of basal insulin administration to avoid peak insulin action during sleep hours if you're using multiple daily injections in addition to pump therapy. 1
Common Pitfalls to Avoid
The most common mistake is running supraphysiological basal rates (higher than physiologically required) in an attempt to lower average glucose. 2 This approach inevitably leads to nocturnal hypoglycemia. Your basal rate should maintain stable glucose levels during fasting periods, not actively lower elevated glucose - that's the job of correction boluses.
Another critical error is waiting too long to make adjustments. With glucose levels in the 30s, you're at risk for seizures, cardiac arrhythmias, and the "dead-in-bed syndrome." 8 Almost 50% of all severe hypoglycemic episodes occur at night during sleep. 8