Diabetes: Dealing with low blood sugar from medicines
What is a low blood sugar (hypoglycemia) emergency?
Low blood sugar (hypoglycemia) means that the level of sugar (glucose) in your blood has dropped below what your body needs to function normally. When your blood sugar level drops below 70 milligrams per deciliter (mg/dL), you most likely will have symptoms, such as feeling tired, weak, or shaky. Symptoms of low blood sugar usually develop quickly.
- If your blood sugar level drops just slightly below a safe range, you may have symptoms of mild low blood sugar. If you eat something that contains sugar, your symptoms may last only a short time. If you have had diabetes for many years, you may not realize your blood sugar is low until it drops very low. This is called hypoglycemia unawareness.
- If your blood sugar level continues to drop (usually below 40 mg/dL), your behavior may change. Symptoms of moderate low blood sugar may start. You may become too weak or confused to eat something to raise your blood sugar level.
- If your blood sugar level drops very low (below 20 mg/dL), you may lose consciousness or have a seizure. If you have symptoms of severe low blood sugar, you need medical care immediately.
What causes low blood sugar?
Low blood sugar levels can be caused by some oral medicines used to treat diabetes and also by insulin shots. This is more likely to happen if you eat less food than usual, exercise, or do intense physical work. Very low blood sugar levels most often develop rapidly (in 10 to 15 minutes) when a person has skipped a meal and is doing intense physical work. Reduced kidney function can prolong the action of diabetes medicine, possibly making low blood sugar levels more frequent.
Usually, blood sugar levels in people who take diabetes medicine drop only low enough to cause mild symptoms. Very low blood sugar levels usually do not occur in people with diabetes who do not take insulin shots. Some pills used to treat type 2 diabetes are more likely to cause low blood sugar than others.
Low blood sugar levels can occur if you:
- Take too many of your sulfonylurea pills in a day or take your doses too close together.
- Continue to take your full dose of sulfonylurea pills when you are not going to eat your usual amount of food.
- Exercise strenuously without eating enough food.
- Drink too much alcohol, especially on an empty stomach.
- Take certain other medicines that lower blood sugar. Some medicines that you can buy without a prescription can affect blood sugar. Talk with your doctor about your prescription and nonprescription medicines and the risk of developing very low blood sugar levels.
Test Your Knowledge
Low blood sugar means that the level of sugar in the blood has dropped below what the body needs to function normally—usually below 70 mg/dL.
Very low blood sugar levels (below 20 mg/dL) are emergency situations and require immediate care.
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Why do I need to deal with low blood sugar emergencies?
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| Author: | Caroline Rea, RN, BS, MS | Last Updated: August 14, 2007 |
| Medical Review: | Caroline S. Rhoads, MD - Internal Medicine Matthew I. Kim, MD - Endocrinology & Metabolism | |
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