How To Treat Low Blood Sugar (Hypoglycemia)

Man having a snack and checking his blood sugar

If you think you have low blood sugar, be sure to check it.

Keeping your blood sugar levels on target as much as possible can help prevent or delay long-term, serious health problems. While this is important, closely managing your blood sugar levels also increases your chance for low blood sugar (hypoglycemia). Blood sugar below 70 mg/dL is considered low. If you think you have low blood sugar, check it. If you aren’t able to check it, go ahead and treat it.

Untreated low blood sugar can be dangerous, so it’s important to know what to do about it and to treat it immediately.

The 15-15 Rule

If you have low blood sugar between 55-69 mg/dL, you can treat it with the 15-15 rule: have 15 grams of carbs. Check it after 15 minutes. Repeat if you’re still below your target range.

The 15-15 Rule

For low blood sugar between 55-69 mg/dL, raise it by following the 15-15 rule: have 15 grams of carbs and check your blood sugar after 15 minutes. If it’s still below your target range, have another serving. Repeat these steps until it’s in your target range. Once it’s in range, eat a nutritious meal or snack to ensure it doesn’t get too low again.

These items have about 15 grams of carbs:

  • 4 ounces (½ cup) of juice or regular soda.
  • 1 tablespoon of sugar, honey, or syrup.
  • Hard candies, jellybeans, or gumdrops (see food label for how much to eat).
  • 3-4 glucose tablets (follow instructions).
  • 1 dose of glucose gel (usually 1 tube; follow instructions).

Tips to keep in mind:

  • It takes time for blood sugar to rise after eating. Give some time for treatment to work. Following the 15-15 rule helps.
  • Young children usually need less than 15 grams of carbs, especially infants and toddlers. Ask your doctor how much your child needs.
  • You should avoid eating a carb with lots of fiber, such as beans or lentils, or a carb that also has fat, such as chocolate. Fiber and fat slow down how fast you absorb sugar.
  • Check your blood sugar often when lows are more likely, such as when the weather is hot or when you travel.

Treating Severely Low Blood Sugar

Blood sugar below 55 mg/dL is considered severely low. You won’t be able to treat it using the 15-15 rule. You also may not be able to check your own blood sugar or treat it by yourself, depending on your symptoms. Make sure your family members, friends, and caregivers know your signs of low blood sugar so they can help treat it if needed.

Injectable glucagon is the best way to treat severely low blood sugar. A glucagon kit is available by prescription. Speak with your doctor to see if you should have a kit. Be sure to learn how and when to use it. Let family members and others close to you know where you keep the glucagon kit and make sure they’ve been trained in how to use it too.

It’s important to contact a doctor for emergency medical treatment immediately after receiving a glucagon injection. If a person faints (passes out) due to severely low blood sugar, they’ll usually wake up within 15 minutes after a glucagon injection. If they don’t wake up within 15 minutes after the injection, they should receive one more dose. When the person is awake and able to swallow:

  • Feed the person a fast-acting source of sugar (regular soft drink or fruit juice).
  • Then, have them eat a long-acting source of sugar (crackers and cheese or a sandwich with meat).

It’s also important that friends, family, co-workers, teachers, coaches, and other people you may be around often know how to test your blood sugar and treat severely low blood sugar before it happens.

A medical ID, usually a bracelet or necklace, can be critical in keeping you safe and healthy. Emergency medical technicians are trained to look for a medical ID when caring for someone who can’t speak for themselves.

When To Call 911

If any of the following happens, your friend, relative, or helper should call 911:

  • You pass out and no glucagon is available.
  • You need a second dose of glucagon.
  • You had glucagon but are still confused.
  • Your blood sugar stays too low 20 minutes after treatment or doesn’t respond to your usual treatments.

Or call 911 anytime you are concerned about your severely low blood sugar.

After You Have Low Blood Sugar

If your low blood sugar was mild (between 55-69 mg/dL), you can return to your normal activities once your blood sugar is back in its target range.

After you have low blood sugar, your early symptoms for low blood sugar are less noticeable for 48 to 72 hours. Be sure to check your blood sugar more often to keep it from getting too low again, especially before eating, physical activity, or driving a car.

If you used glucagon because of a severe low (54 mg/dL or below), immediately call your doctor for emergency medical treatment. If you have had lows several times close together (even if they’re not severe), you should also tell you doctor. They may want to change your diabetes plan.

Know Your Numbers

If you continue to have low blood sugar episodes, share your blood sugar, insulin, physical activity, and food logs with your doctor. They may be able to identify patterns and help prevent lows by adjusting the timing and amount of your insulin, physical activity, and meals.

Page last reviewed: January 20, 2021