What is hypoglycemia?


Hypoglycemia is when blood glucose levels get too low. People with hypoglycemia might feel shaky, dizzy, sweaty, and irritable. They might also have tingly lips and a headache.

Hypoglycemia is a diabetic emergency caused by too little sugar in the blood. This can occur when a person takes too much insulin, eats too little food, or overexerts him or herself. Hypoglycemia is dangerous because extremely low blood sugar levels quickly can become life threatening.

Hypoglycemia is a condition that occurs when one's blood glucose is lower than normal, usually less than 70 mg/dL. Signs include hunger, nervousness, shakiness, perspiration, dizziness or light-headedness, sleepiness, and confusion. If left untreated, hypoglycemia may lead to unconsciousness. Hypoglycemia is treated by consuming a carbohydrate-rich food such as a glucose tablet or juice. It may also be treated with an injection of glucagon if the person is unconscious or unable to swallow. Hypoglycemia is also called an insulin reaction.

Emilia Klapp
Nutrition & Dietetics Specialist

Hypoglycemia is a common blood-sugar disorder. It occurs when blood-sugar levels rise and fall at irregular rates, affecting the metabolism of energy. In general, hypoglycemia means low blood glucose. This causes low energy, fatigue, sleepiness, difficulty concentrating, poor memory, and irritability.

Hypoglycemia refers to low blood sugar. Normal blood sugar, or blood glucose, falls between 70 and 110 milligrams of glucose per deciliter of blood. When blood sugar falls below 70, symptoms of hypoglycemia may begin, although they may not become noticeable until blood sugar is below 60 mg/dL. The severity of hypoglycemia depends on how low the blood sugar falls.

Dr. Jack Merendino, MD

Hypoglycemia is, simply, abnormally low blood sugar levels. It's not really defined by a number, though a sugar level under 65 is usually too low and much lower is almost always a concern. It's often caused by a mismatch between your insulin dose (or other medications that cause insulin levels to rise) and meals or exercise. In other words, you have too much insulin in your system and are putting away so much blood sugar that the level falls too low.

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Continue Learning about Hypoglycemia


Hypoglycemia is when your body does not release glucose stored in your liver to raise your blood sugar. This is your body's main source of energy. The brain needs sugar to do its job properly. So signs that your blood sugar level ...

is too low can include dizziness, being easily confused, having blurred or double vision, and passing out. Hypoglycemia isn't a disease. It indicates another health problem, and is most often caused by side effects from diabetes medications. Other causes of hypoglycemia include kidney and liver illnesses, eating disorders and drinking a lot of alcohol without eating. Eating or drinking something with carbohydrates can help raise the blood sugar and stop the symptoms. You can also take glucose pills. If you pass out, it's important to get immediate medical treatment.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.