Long-acting insulin, also known as basal insulin, provides a continuous, low-level supply throughout the day and night. This steady release helps maintain consistent blood glucose levels between meals and overnight. Given its continuous action, decisions to adjust or temporarily withhold a dose require careful consideration due to the potential for significant shifts in blood sugar.
Understanding Long-Acting Insulin’s Role
Long-acting insulin mimics the natural, steady release from a healthy pancreas. Unlike rapid-acting insulin, which is taken with meals to manage immediate blood sugar spikes, long-acting insulin does not have a peak effect; instead, it works to regulate blood sugar levels at a consistent rate over an extended period, typically 16 to 24 hours. This continuous basal support is crucial for preventing hyperglycemia, independent of food intake. Consequently, any decision to reduce or “hold” this insulin type means removing this foundational glucose control, which can lead to a rise in blood sugar levels.
Specific Situations for Dose Consideration
There are particular circumstances where adjusting a long-acting insulin dose might be considered, though such decisions should always be made with guidance from a healthcare professional. One common situation involves hypoglycemia, or low blood sugar. If an individual experiences severe or frequent episodes of low blood sugar, especially overnight, it may indicate that the long-acting insulin dose is too high. Symptoms of hypoglycemia can include shakiness, dizziness, sweating, and headache, and if blood sugar drops below 70 mg/dL, immediate treatment with 15 grams of fast-acting carbohydrates is necessary. A healthcare provider might then advise a temporary reduction or adjustment to the long-acting insulin dose to prevent future lows.
Periods of reduced food intake or fasting also warrant consideration for long-acting insulin adjustment. If an individual is ill with vomiting or diarrhea, preparing for surgery, or engaging in prolonged fasting, their usual insulin dose might be excessive due to a significant decrease in calorie consumption. In such cases, the body’s need for background insulin may decrease. For instance, before a short fasting period for a procedure, a healthcare provider might recommend reducing the morning dose of long-acting insulin by 20%. For longer fasting periods, a 50% reduction of the usual dose might be suggested.
Unusual physical activity can also impact insulin requirements. Intense or prolonged exercise increases the body’s sensitivity to insulin and can lower blood sugar levels for several hours, sometimes up to 24-48 hours, after the activity. While rapid-acting insulin adjustments are more common for exercise, some individuals may need to reduce their long-acting insulin, particularly for extended events like long hikes or bike rides. A reduction of 10% to 20% of the long-acting insulin dose, especially the bedtime dose after an active day, might be necessary to prevent overnight hypoglycemia.
Finally, certain medical conditions, such as kidney or liver impairment, can affect how the body processes and clears insulin. In advanced kidney failure, the body’s ability to excrete insulin decreases, potentially leading to a longer duration of insulin action and an increased risk of hypoglycemia. This may necessitate a reduction in insulin dosage, sometimes by as much as 50% for severe impairment. These are complex medical situations where any insulin adjustment must be strictly managed by a healthcare team.
Monitoring and Next Steps After Adjusting
After any adjustment to a long-acting insulin dose, frequent blood sugar monitoring becomes even more important. Checking blood glucose levels several times a day, such as before meals and at bedtime, helps to assess the impact of the change and detect any trends towards high or low blood sugar. Continuous glucose monitoring (CGM) systems can provide valuable data on glucose patterns throughout the day and night, offering a more complete picture of how the body is responding. This data helps to determine if further adjustments are needed.
If blood sugar levels begin to rise significantly after reducing or holding long-acting insulin, especially if they are consistently above 250 mg/dL, testing for ketones is advised. Ketones are chemicals produced when the body breaks down fat for energy due to insufficient insulin, and their presence can indicate a risk of diabetic ketoacidosis (DKA), a serious condition. Staying well-hydrated by drinking non-carbohydrate fluids is also crucial, particularly if blood sugars are high or if feeling unwell, to help flush out ketones.
Any changes made to an insulin regimen and the resulting blood sugar readings should be communicated promptly to the healthcare team. Re-establishing the usual long-acting insulin dose once the temporary situation has resolved should also be done under medical guidance.
When to Seek Professional Guidance
Certain symptoms and situations demand immediate professional medical attention. If persistent high blood sugar levels are accompanied by moderate to high ketone levels, or symptoms like nausea, vomiting, abdominal pain, rapid breathing, confusion, or fruity-smelling breath, it could indicate diabetic ketoacidosis (DKA), which is a medical emergency. In such cases, contacting emergency services or going to the nearest emergency department is necessary.
Any significant or long-term changes to an insulin regimen should always be discussed with a doctor or diabetes educator before implementation. This information is for educational purposes and cannot replace personalized medical advice. Regular follow-up appointments with a healthcare team are important for reviewing the insulin regimen, addressing any concerns, and ensuring overall diabetes management remains optimized.