Low blood sugar is a condition that occurs when the body's blood sugar (glucose) decreases and is too low.
Blood sugar below 70 mg/dL (3.9 mmol/L) is considered low. Blood sugar at or below this level can be harmful.
The medical name of low blood sugar is hypoglycemia.
Hypoglycemia; Insulin shock; Insulin reaction; Diabetes - hypoglycemia
Insulin is a hormone made by the pancreas. Insulin is needed to move glucose into cells where it is stored or used for energy. Without enough insulin, glucose builds up in the blood instead of going into the cells. This leads to symptoms of diabetes.
Low blood sugar occurs due to any of the following:
Low blood sugar is common in people with diabetes who are taking insulin or certain other medicines to control their diabetes. However, many other diabetes medicines do not cause low blood sugar.
Exercise can also lead to low blood sugar in people taking insulin to treat their diabetes.
Babies born to mothers with diabetes may have severe drops in blood sugar right after birth.
In people who do not have diabetes, low blood sugar may be caused by:
Symptoms you may have when your blood sugar gets too low include:
In many people with diabetes, low blood sugar causes nearly the same symptoms every time it happens. Not everybody feels low blood sugar symptoms the same way.
Some symptoms, like hunger or sweating, occur when blood sugar is only slightly low. More severe symptoms, such as unclear thinking or seizure, occur when the blood sugar is much lower (less than 40 mg/dL or 2.2 mmol/L).
Even if you do not have symptoms, your blood sugar could still be too low (called hypoglycemic unawareness). You may not even know you have low blood sugar until you faint, have a seizure, or go into a coma. If you have diabetes, ask your health care provider if wearing a continuous glucose monitor can help you detect when your blood sugar is getting too low to help prevent a medical emergency. Some continuous glucose monitors can alert you and other people that you designate when your blood sugar decreases below a set level.
If you have diabetes, keeping good control of your blood sugar can help prevent low blood sugar. Talk to your provider if you're not sure about the causes and symptoms of low blood sugar.
The goal of treatment is to correct your low blood sugar level. It is also important to try and identify the reason why the blood sugar was low to prevent another low blood sugar episode from happening.
If you have diabetes, it is important that your provider teaches you how to treat yourself for low blood sugar. Treatment may include:
Or you may have been told to give yourself a shot of glucagon. This is a medicine that raises blood sugar.
If low blood sugar is caused by an insulinoma, surgery to remove the tumor will be recommended.
Ulrik Bjergaard-Pedersen practices in Hillerød, Denmark. Bjergaard-Pedersen is rated as an Elite expert by MediFind in the treatment of Low Blood Sugar. He is also highly rated in 4 other conditions, according to our data. His top areas of expertise are Low Blood Sugar, Type 1 Diabetes (T1D), Type 2 Diabetes (T2D), and Maturity Onset Diabetes of the Young.
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Elizabeth Seaquist is an Infectious Disease specialist and an Endocrinologist in Minneapolis, Minnesota. Seaquist has been practicing medicine for over 41 years and is rated as an Elite expert by MediFind in the treatment of Low Blood Sugar. She is also highly rated in 4 other conditions, according to our data. Her top areas of expertise are Low Blood Sugar, Type 1 Diabetes (T1D), Type 2 Diabetes (T2D), and Maturity Onset Diabetes of the Young. She is licensed to treat patients in Minnesota. Seaquist is currently accepting new patients.
Severe low blood sugar is a medical emergency. It can cause seizures and brain damage. Severe low blood sugar that causes you to become unconscious is called hypoglycemic or insulin shock.
Even one episode of severe low blood sugar may make it less likely for you to have symptoms that allow you to recognize another episode of low blood sugar. Episodes of severe low blood sugar can make people afraid to take insulin as prescribed by their provider.
If signs of low blood sugar do not improve after you have eaten a snack that has sugar:
Get medical help right away for a person with diabetes or low blood sugar who:
Summary: Hypoglycemia is the term used to refer to lower than normal levels of blood sugar. This study will continue to research the causes of hypoglycemia. Patients involved in the study will be admitted to the Clinical Center of the National Institutes of Health and undergo tests for evaluating blood sugar. Patients will be required to refrain from eating for a set period of time and will undergo blood t...
Summary: Use of real-time continuous glucose monitoring (RT-CGM) systems in inpatient settings especially during the COVID-19 pandemic, may allow hospital staff to remotely monitor glucose while reducing viral exposure and preserving use of PPE. RT-CGM may be of benefit to inpatients with unstable glycaemia and at risk of severe hypoglycaemia, as it can automatically alert the treating clinical team of hyp...
Published Date: February 01, 2022
Published By: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
American Diabetes Association Professional Practice Committee. 6. Glycemic Targets: Standards of Medical Care in Diabetes-2022. Diabetes Care. 2022;45(Suppl 1):S83-S96. PMID: 34964868 pubmed.ncbi.nlm.nih.gov/34964868/.
Cryer PE, Arbeláez AM. Hypoglycemia. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 38.