In this section, you will find:
Why am I Having Low Blood Sugars?
Possible causes include:
- Eating less carbohydrate than anticipated
- Excessive insulin
- Increased activity or exercise
- Weight Loss
- Delayed eating after taking mealtime insulin
- Delayed stomach (gastric) emptying
- Fear of complications
- Taking the wrong insulin by mistake
- Drinking alcohol
- Increased insulin sensitivity
- Use of Incretin based therapies
Eating less carbohydrate than anticipated
Sometimes we don’t eat what we plan to, or we miscount carbohydrates because we don’t know the carbohydrate content of the food. When this happens, a low blood sugar may occur.
The solution: If you eat less than expected, make up the “missing” grams of carbohydrate by eating them as fresh fruit or dextrose tablets. If you are not sure of the carbohydrate content of the food, check you blood sugar more often and be prepared to take supplemental sugar.
Excessive insulin
Your low blood sugars may stem from taking too much insulin. The clue is having a pattern of repeated low blood sugars at night or upon awakening, or before or after meals.
The solution: Consult with your medical provider regarding whether you should decrease your insulin dose.
Increased activity or exercise
Exercise generally makes the body more sensitive to the action of insulin.
The solution: Scale back insulin doses, and increase carbohydrate consumption in order to prevent low blood sugar. Consult your diabetes medical team about any dose adjustments.
Weight Loss
Weight loss makes the body more sensitive to the action of insulin. Weight loss can dramatically reduce your insulin dose requirement
The solution: Consult your medical provider about reducing your insulin dose.
Delayed eating after taking mealtime insulin
Life is full of delays, so it’s not uncommon to anticipate eating a meal, take your insulin and then have something happen that delays the meal. This is particularly true when going out to eat.
The solution: Take rapid-acting insulin only when your meal is right in front of you. Seeing what is actually being served also will also help you to choose the best insulin dose. And try to eat your meals at predictable times
Delayed stomach (gastric) emptying
This condition can be caused by a high fat or high fiber meal, stomach neuropathy (gastroparesis), or medications such as exenatide and Pramlintide. In each case, the insulin acts before the carbohydrate portion of the meal is released into the intestine and absorbed.
The solution: Avoid high fat and high fiber meals. If gastroparesis is present, eat small, relatively liquid meals. Consume carbohydrate containing foods in the beginning of the meal. If you are taking exenitide or Pramlintide, reduce your insulin dose. Always consult with your medical provider regarding any insulin dose adjustment.
Fear of complications
For some individuals the fear of complications from high blood glucose is so overwhelming that they prefer risking low blood sugar to the health consequences of chronic highs. This is a dangerous tradeoff. Low blood sugar can cause immediate, even life-threatening harm.
The solution: Reduce the insulin dose until the low blood sugars are eliminated.
Taking the wrong insulin by mistake
Sometimes people take rapid-acting insulin instead of long-acting insulin by mistake and get a low blood sugar. This can be a problem with insulin pens as they can look alike. Clear long-acting insulin, such as glargine or detemir, can be confused with clear short- or rapid-acting insulin.
The solution: Always double check that you are injecting the correct insulin.
Drinking alcohol
Alcohol can reduce the amount of glucose produced by the liver, and can put you at risk for a low blood sugar.
The solution: Drink alcohol in moderation. Eat carbohydrates when you drink alcohol. Check your blood sugar.
Increased insulin sensitivity
Losing weight and increased activity can both increase your sensitivity to insulin leading to a decrease in your insulin needs. Other less common causes of reduced insulin requirements include: kidney problems, low thyroid and loss of glucagon due to a decrease in pancreatic function.
The solution: Discuss with your diabetes team how your other medical diagnoses may affect your diabetes management.
Use of Incretin based therapies (exenatide, sitigliptin or Pramlintide)
Incretin based therapy (exenatide, sitigliptin) or Pramlintide will lower blood sugars after you eat. In combination with insulin, their use may result in a low blood sugar.
The solution: Decrease the insulin dose, and as needed, the incretin or pramlintide dose. Consult your medical provider for specific recommendations regarding medication dose adjustment.
Why am I having high blood sugars?
Possible causes include:
- Incorrect carbohydrate counting
- “Out-eating” the insulin
- Inadequate insulin dose
- Rebound from a low blood glucose
- Delayed stomach emptying
- Under-insulinization because of fear of low blood sugars
- Failure to monitor blood glucose levels
- “Needle phobia”
- Taking medications that cause insulin resistance
- Inactivity
- Increase in stress hormones
- Bad (spoiled) insulin
- Incorrect insulin injection technique
- Injecting into scarred or overused areas
- Taking the wrong insulin by mistake
Incorrect carbohydrate counting
If your mealtime carbohydrate count is wrong, your insulin dose will be too. This is particularly true when eating out or when eating foods that don’t have nutrition labels.
The solution: Learn more about carbohydrate counting. Weigh and measure your food. Eat foods with carbohydrate counts that you already know. Research nutrition information online for food options at restaurants and chain outlets.
“Out-eating” the insulin
It’s not always easy to anticipate how much you will actually eat during a meal. However, missing the mark has the same affect as if you miscounted carbohydrates. Moreover, there are individual limits on how much mealtime carbohydrate can realistically be covered.
The solution: If you decide to eat more than you planned, you will need to take more insulin to cover the additional carbohydrates. In general it’s wise to limit your mealtime consumption of carbohydrate to less than 60-75g or to whatever has been recommended by your nutritionist. If you have a special occasion coming up, be sure to discuss any special “party meal” or “banquet” medication dose adjustment with your medical provider.
Inadequate insulin dose
An insufficient insulin dose can cause chronically elevated blood sugar readings. If the blood sugars are too high overnight, upon awakening, or before or after meals, you may not be getting enough insulin.
The solution: Consider increasing the amount of your insulin dose in consultation with your diabetes medical team.
Rebound from a low blood glucose
The body’s natural response is to maintain balance. Low blood sugar is no exception. The body releases glucose counter-regulatory hormones that raise the blood sugar. The effects of these hormones may last for 6-8 hours. To stop the highs, you need to stop the lows.
The solution: Adjust the insulin doses to prevent low blood sugars. Discuss with your medical provider the causes of why you are getting low blood sugars.
Delayed stomach emptying
This condition can be caused by a high fat or high fiber meal, stomach neuropathy (gastroparesis), or by medications such as exenatide or pramlintide. In each case, the insulin action is almost over by the time the carbohydrate portion of the meal is released into the intestine and absorbed. The classic pattern is a low blood sugar in the early part of the meal followed by a high blood sugar for many hours after.
The solution: Avoid high fat or high fiber meals. If gastroparesis is present, eat small, relatively liquid meals and consume carbohydrate foods first.
Under-insulinization because of fear of low blood sugars
The symptoms of low blood sugar can be very uncomfortable, so it’s no surprise that people sometimes overreact by taking less insulin than is necessary.
The solution: Gradually increase your insulin doses so that you become familiar with what amount is best. Consult with your medical provider regarding any insulin dose adjustments.
Failure to monitor blood glucose levels
If you don’t check your blood sugar regularly, you may be unaware of high blood sugar.
The solution: Check your blood sugar at regular intervals (no less than 4 times a day), and adjust your insulin dose as recommended by your provider.
“Needle phobia”
Some people just don’t like taking insulin injections – even after years of having diabetes and knowing how important they are.
The solution: Consider using an alternative delivery system, such as an insulin pump or pen.
Taking medications that cause insulin resistance
Occasionally it is necessary to take medications, such as steroids or niacin, that lead to insulin resistance.
The solution: Work with your diabetes team to adjust your insulin dose to maintain glucose control.
Inactivity
Any decrease in your usual activity can decrease your insulin sensitivity and increase your insulin requirements.
The solution: Monitor your blood sugar levels closely and adjust your insulin replacement accordingly.
Increase in stress hormones
There are many reasons why your stress hormones might spike: Infections, physical and emotional stress, medical conditions like thyroid or liver disease, pregnancy or puberty.
The solution: Work with your diabetes team to adjust your insulin dose to maintain glucose control.
Bad (spoiled) insulin
Insulin won’t work if it gets too hot or too cold. And it will spoil if the cartridges or vials are left open for too long.
The solution: Look at the package insert and follow the storage instructions. If you think your insulin is spoiled, use a new cartridge or vial. Remember never to place insulin in direct sunlight, leave it in a hot car, or place it too close to the freezer section in the refrigerator. And keep your insulin supplies with you when traveling.
Incorrect insulin injection technique
There is a proper technique for injecting insulin. Technique is important because things like air bubbles in the syringe or cartridge, leakage from the injection site or simply measuring out the wrong amount, can result in an incorrect insulin dose.
The solution: Check for bubbles and, if you use a pen device, clear the air from the syringe or cartridge with a test dose before administering the insulin. To prevent leakage from the injection site, count to 10 before withdrawing the needle from the skin. And double check the dose before injecting.
Injecting into scarred or overused areas
Repeated insulin injections in the same area can lead to scarring, which may interfere with insulin absorption.
The solution: Avoid overusing one area. Rotate your insulin injection sites.
Taking the wrong insulin by mistake
Sometimes people get a high blood sugar reading because they mistakenly took the long-acting insulin instead of short or rapid- acting insulin. This is a particular problem when you’re using pens to administer insulin since all pens – including those for long-acting agents such as Lantus and Levemir – tend to look alike.
The solution: Spend a moment to make sure you are taking the right kind of insulin.
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