Hypoglycemia means low blood glucose, or blood sugar. Your body needs glucose to have enough energy. After you eat, your blood absorbs glucose. If you eat more sugar than your body needs, your muscles, and liver store the extra. When your blood sugar begins to fall, a hormone tells your liver to release glucose.
In most people, this raises blood sugar. If it doesn't, you have hypoglycemia, and your blood sugar can be dangerously low. Signs include
- Difficulty speaking
- Feeling anxious or weak
In people with diabetes, hypoglycemia is often a side effect of diabetes medicines. Eating or drinking something with carbohydrates can help. If it happens often, your health care provider may need to change your treatment plan.
You can also have low blood sugar without having diabetes. Causes include certain medicines or diseases, hormone or enzyme deficiencies, and tumors. Laboratory tests can help find the cause. The kind of treatment depends on why you have low blood sugar.
NIH: National Institute of Diabetes and Digestive and Kidney Diseases
- Is Low Blood Glucose (Hypoglycemia) Dangerous? (Joslin Diabetes Center)
- What Can I Do to Prevent Serious Hypoglycemic Episodes When I Am Hypoglycemic Unaware? (Joslin Diabetes Center)
- Diabetic Hypoglycemia (Mayo Foundation for Medical Education and Research)
- Hypoglycemia (Low Blood Sugar) in Diabetes Mellitus (UpToDate)
- Is Hyperinsulinemia a Form of Diabetes? (Mayo Foundation for Medical Education and Research)
- Nondiabetic Hypoglycemia (Hormone Health Network) Also in Spanish
- Reactive Hypoglycemia (Mayo Foundation for Medical Education and Research)
- Genetics Home Reference: 3-hydroxyacyl-CoA dehydrogenase deficiency (National Library of Medicine)
- Genetics Home Reference: congenital hyperinsulinism (National Library of Medicine)
- Genetics Home Reference: familial glucocorticoid deficiency (National Library of Medicine)
- Genetics Home Reference: glycogen storage disease type VI (National Library of Medicine)
Statistics and Research
- Link between Hypoglycemia and Cardiac Arrhythmias: An Answer to Why Tight Glycemic Control May Increase Mortality in People with Diabetes (American Diabetes Association)
- Patient Access to Research (American Diabetes Association)
- ClinicalTrials.gov: Hypoglycemia (National Institutes of Health)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
- Article: Late presentation of necrotizing enterocolitis associated with rotavirus infection in...
- Article: Continuous Glucose Monitoring in Very Preterm Infants: A Randomized Controlled...
- Article: Hypothalamic Glucose Transport in Humans During Experimentally Induced Hypoglycemia-Associated Autonomic...
- Hypoglycemia -- see more articles
Find an Expert
- American Diabetes Association
- Directory of Diabetes Organizations (National Institute of Diabetes and Digestive and Kidney Diseases) - PDF
- National Institute of Diabetes and Digestive and Kidney Diseases
- What Is Hypoglycemia? (Nemours Foundation)
- Diabetes - low blood sugar - self-care (Medical Encyclopedia) Also in Spanish
- Drug-induced hypoglycemia (Medical Encyclopedia) Also in Spanish
- Insulin C-peptide (Medical Encyclopedia) Also in Spanish
- Low blood sugar (Medical Encyclopedia) Also in Spanish
- Low blood sugar - newborns (Medical Encyclopedia) Also in Spanish