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What are the signs and symptoms of hypoglycemia?

Medically reviewed by Leigh Ann Anderson, PharmD. Last updated on Oct 16, 2023.

Official answer


Signs and symptoms of hypoglycemia (low blood sugar) include:

  • feeling hungry
  • feeling nervous or worried
  • trembling or shaky feeling
  • sweating
  • fast heart rate
  • pale skin
  • dizziness or light-headedness
  • sleepiness
  • confusion
  • passing out (if low blood sugar left untreated)

Hypoglycemia occurs in people when the level of sugar in their blood gets too low.

If low blood sugar is not treated, it can become serious. You may have symptoms like feeling weak, blurry vision, severe confusion, passing out (unconscious) or having a seizure. “Insulin shock” is a term used to describe severe hypoglycemia that results in unconsciousness.

When do you get hypoglycemia?

If you have diabetes, your blood sugar may get too low when you:

  • go without eating
  • take too much medicine to treat diabetes
  • exercise too much
  • do not eat enough food to keep your “sugar” levels where they need to be
  • drink too much alcohol

Hypoglycemia can occur when your blood sugar level drops below 70 mg/dL, but this may vary among people. Hypoglycemia may occur in people with or without diabetes, but it is most common if you have diabetes.

People who do not have diabetes may have low blood sugar due to other medical conditions, such as tumors on their pancreas, liver or kidney disease, after weight loss surgery, or an eating disorder. Taking certain medicines and drinking alcohol may also be a risk.

How do you treat low blood sugar?

Follow your doctor’s instructions on how to treat low blood sugar. In general, low blood sugar in people with or without diabetes is treated the same way.

You should always carry a quick source of sugar with you, as low blood sugar should be treated as soon as possible. Hypoglycemia is treated by consuming a fast-acting source of sugar such as:

  • glucose tablets or gel
  • ½ cup of fruit juice or a ½ cup of regular (not sugar-free or diet) soda
  • one tablespoon of sugar or honey
  • 6 to 8 hard candies

Do not use products that are labeled as “sugar-free” to treat hypoglycemia.

Check your blood sugar after 15 minutes and if it is still below 70 mg/dL, eat another fast-acting source of sugar. Once your blood sugar is normal, have a snack or meal like crackers with cheese to help keep your blood sugar levels normal and replenish glucose stores.


You may need to be treated with glucagon if you pass out or are unable to swallow. Glucagon is a hormone that can quickly increase your blood sugar. It's a prescription medicine and comes as an injection, auto-injector pen, pre-filled syringe or intranasal (nose) powder.

Read the detailed Instructions for Use that comes with your glucagon treatment. Your doctor will show you, and your caregiver or family member, how and when to use this medicine. Make sure that you, your family, and close friends know how to use glucagon the right way before you have an episode of severe low blood sugar.

Glucagon is available as a brand and generic product. Brands names include:

Call for emergency assistance immediately after administering the dose. If the person with severe low blood sugar does not respond after 15 minutes, another dose may be given, if available.

Get emergency help right away (in the US or Canada call 911) if you are still feeling confused 15 minutes after a dose of glucagon, are unconscious but there is no glucagon available, or still have low blood sugar after a treatment. Do not drive yourself to the hospital. Also tell your doctor each time you have used glucagon.

When you have responded to glucagon treatment and you can safely swallow, your caregiver or family member should give a source of sugar (carbohydrates) to help prevent another episode of low blood sugar. This may include a fast-acting source of sugar (such as fruit juice) AND a longer-acting source of sugar (such as crackers with cheese or peanut butter).

Learn more: List of Medicines to Treat Hypoglycemia

Related questions

How can I to prevent hypoglycemia?

  • Learn at what levels and when you need to treat your low blood sugar. Your doctor will tell you this information.
  • Check your blood sugar often, as directed by your doctor.
  • Know the symptoms of hypoglycemia and treat it early to prevent serious outcomes

This is not all the information you need to know about hypoglycemia (low blood sugar) and does not take the place of your doctor's instructions. Discuss this information and any questions you have with your doctor or other health care provider.

  • Patient education: Low blood sugar in people with diabetes (The Basics). Up To Date. Accessed Oct. 24, 2021
  • Patient education: Low blood sugar in people without diabetes (The Basics). Up To Date. Accessed Oct. 24, 2021 at

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