Tight Blood Sugar Control Can Result in Hypoglycemia

What Can Cause Low Blood Sugar and How to Prevent it

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Clinical guidelines recommend that people with diabetes keep their blood sugars controlled to prevent long-term complications. Sometimes trying to avoid high blood sugars can result in hypoglycemia - low blood sugar. While it may seem like a good thing for your blood sugar to be  low, tight blood sugar control resulting in low blood sugars is not a good thing. If not treated promptly, a hypoglycemic event can result in an emergency situation.

 Chronically low blood sugars are also problematic, especially for those who do not recognize the symptoms of low blood sugars. If you are someone who experiences low blood sugars frequently, you may become unable to feel symptoms of low blood sugars, a condition referred to as hypoglycemia unawareness. The inability to feel symptoms, such as sweating, shaking, increased heart beat, anxiety or hunger, can make you incapable of treating the low which can result in unconsciousness or even death. 

It's normal to have a low blood sugar from time to time, but in the event that you are experiencing frequent low blood sugars, it is extremely important that you communicate it to your physician so that your medications may be changed as needed. It may also be beneficial for your physician to change your blood sugar targets. Preventing low blood sugars is important for safety and can help improve your quality of life.


Who is at Greatest Risk for Low Blood Sugars? 

Elderly, those with hypoglycemia unawareness and children with Type 1 diabetes seem to be the most vulnerable to hypoglycemia. This is one of the reasons why blood sugar goals are likely to be less stringent dependent on age. If you are not sure what your blood sugar targets are, you should ask your doctor or certified diabetes educator.

For more information on blood sugar targets: Blood Sugar Targets Differ for Individuals

People with diabetes who take insulin or oral hypoglycemic agents are also at increased risk of having low blood sugars. Receiving diabetes self-management education can help you to understand how your medicines work -  when you should take them, and when you should skip them. 

Why Would By Blood Sugar Drop Too Low? 

A Delayed or Skipped Meal: For those people with diabetes who take insulin or oral diabetes medicines that stimulate the release of insulin from the pancreas, delaying or skipping a meal when taking your medicine can result in a low blood sugar. When possible, aim to eat on a schedule and try to take your medicines around the same time daily. While skipping meals is not ideal, it does happen. Ask you doctor if you should skip your medicine if you skip a meal. 

You Took Too Much Medicine: Injecting a higher dose of insulin than normal or doubling up on your oral medicines can cause your blood sugar to drop too low. Not adhering to your medication regimen can cause extreme fluctuations in your blood sugar. It can become difficult to figure out a pattern or make changes to your medications without any consistency.

If your current medication regimen is resulting in extreme fluctuations in your blood sugars, keep a blood glucose log and call your physician or bring it to your next appointment so they can help assist you to make a medication change. Once you feel comfortable, you may be able to adjust your medicine on your own. 

Exercise: Another variable that can affect blood sugar is physical activity. Exercise is a great way to reduce blood sugars, burn calories and strengthen muscles. However, if you exercise without eating or exercise and delay a meal, your blood sugar may drop too low. It's a good idea to always carry a snack with you for before or after a workout.

It's also a good idea to make sure you carry 15 g of fast acting carbohydrate, so that in the event you do have a low blood sugar during a workout, you are able to treat it promptly. 

Weight Loss: If you are overweight, weight loss can help you to lower your blood sugars by making you more sensitive to insulin. Oftentimes, weight loss improves blood sugars so much that people are able to reduce or stop taking their medicines. If you are losing weight and your blood sugars begin to go too low, call your doctor so that you can have your medicines reduced or stopped.  

Decrease in Carbohydrate Intake: One of the biggest determinants of blood sugar control is your carbohydrate intake. Reducing the amount of carbohydrates you eat can reduce your blood sugars. Reducing your carbohydrate intake significantly without changing your medicines can result in hypoglycemia. For example, if you are someone who takes a fixed dose of mealtime insulin and usually eat about 45 g of carbohydrate per meal, then decide to eat a low carbohydrate meal and continue the same dose of insulin may put yourself at risk of having a low blood sugar.  

People with Kidney Disease: One of the complications of diabetes is kidney disease. Elevated blood sugars over time can affect the vessels in the kidneys which can make the kidneys sluggish in filtering minerals, toxins, and medicines. Certain medications that are cleared through the kidney should be avoided or reduced to prevent further damage. And other medicines, such as insulin, may take longer to clear, which means they last in the body for a longer period of time and could cause low blood sugars. 

You Decided to Take Your Medicine: Sometimes people with diabetes visit the doctor with high blood sugars because they are not taking their medicines. As a result, your doctor may continue to increase your medicine in hopes to lower your blood sugars without knowing that you aren't taking it. If one day you decide to take the dose prescribed by your doctor, your blood sugar could crash or drop way too low. To avoid this from happening, be honest with your physicians. If you are not taking your medicine, let them know so that they don't continue to add more medicine to your regimen. Instead, tell them why you are not taking it and perhaps they can find an alternative medication that is more suitable to your lifestyle. For example, if you are not taking your medication because it is too expensive, your doctor can find a cheaper medication or help you to find ways to cut cost. 

Drinking Alcohol: Drinking alcohol can cause low blood sugar especially if you are taking insulin or a medicine that tells your pancreas to make insulin. To prevent low blood sugars, learn how to drink safely:  A Guide to Safe Alcohol Consumption


American Diabetes Association. Standards of Medical Care in Diabetes – 2015. Diabetes Care. 2015 Jan; 38 (Suppl 1): S1-90. 

DaVita. Low Blood Sugar and Chronic Kidney Disease. Accessed on-line. July 30, 2015: http://www.davita.com/kidney-disease/causes/diabetes/low-blood-sugar-and-chronic-kidney-disease/e/7903

Curry, Andrew. "Going Low. This is your brain on hypoglycemia." Diabetes Forecast. July/August. 2015: 46-50. Print.