High Blood Sugar FAQs

glucometer reading high blood sugar

Find possible causes and solutions for high blood sugar here.

Some common causes include:

  • "Out-eating" the insulin
  • Inadequate insulin dose
  • Increase in stress hormones

In this section, you will find:

Why am I having high blood sugars?

Possible causes include:

Incorrect carbohydrate counting

If your mealtime carbohydrate count is wrong, your insulin dose will be incorrect as well. 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 whenever possible. Eat foods with carbohydrate counts that you already know. Research nutrition information online for food options at restaurants and chain outlets.

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“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 effect 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.

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Insufficient insulin coverage of the carbohydrate (ie Inadequate insulin-to-carbohydrate ratio)

It is important to know how many grams of carbohydrate are covered by one unit of insulin – this is your insulin-to-carbohydrate ratio. If you think the ratio is out of balance, ask yourself these questions. Did you count the carbohydrates correctly? Did you take the proper blood sugar correction dose before you ate? Were you more or less active than usual? Under any unusual stress?

The solution: Once you have eliminated these variables, you may need to adjust the insulin-to-carbohydrate ratio to get more insulin at the meal or snack. Consult your medical provider about insulin dose adjustments.

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Inadequate basal insulin dose

An insufficient basal insulin dose can cause a high blood sugar reading. To be sure that this is the cause of your high blood sugar, you’ll need to do some detective work. First, check your blood sugar readings overnight and before meals. These readings are least likely to be affected by meal or correction boluses. Second, check that the insulin-to-carbohydrate ratio, high blood sugar correction, or change in your activity and stress level isn’t causing the high blood sugar.

The solution: Once you have eliminated these variables, if the readings are still high, consider increasing the amount of your basal dose in consultation with your diabetes medical team.

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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.

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Delayed stomach (gastric) emptying

This condition can be caused by a high fat or high fiber meal, stomach neuropathy (gastroparesis), or by medications such as an amylin analog (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.

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Taking too little insulin 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.

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Not monitoring 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.

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“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.

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Taking medications that cause insulin resistance

Occasionally it may be 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.

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Any decrease in your customary 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.

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Weight gain

Increased weight causes resistance to the action of insulin. Weight gain is a very common cause of an increased insulin dose requirement

The solution: Watch your calories and watch your weight. If you find you are gaining weight cut back on how much you are eating and consult with your nutritionist.

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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.

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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. Always keep your insulin supplies with you when traveling.

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Incorrect insulin injection technique

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. There is a proper technique for insulin injection.

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. Double-check the insulin dose before injecting.

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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.

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Taking the wrong insulin by mistake

Sometimes people get a high blood sugar reading because they mistakenly inject long-acting insulin instead of short- or rapid-acting insulin. This is particularly a problem when using pens to administer insulin as all pens (including those for long-acting agents, such as Lantus and Levemir) tend to look alike.

The solution: Develop a system to distinguish the different types of insulin. For example, put a rubber band on the long acting insulin, or flag it with a piece of colored tape or mark it with an indelible ink pen. And always double check the type of insulin before giving an injection.

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