Managing your blood sugar

From testing to lows: know the basics

Testing your blood sugar

When using a mealtime insulin like Humalog®, you must test your blood sugar (glucose). You may need to test before and after meals and at bedtime. Your healthcare provider will tell you when and how often you should test.

Why keep track?

Keeping track of your blood sugar levels will help you and your healthcare providers:

  • Know if you're meeting your blood sugar goals
  • Learn how different foods affect your blood sugar levels
  • Figure out how much insulin you should be taking

Your healthcare provider will tell you what to do if your blood sugar is high or low. If you take too much Humalog, your blood sugar may fall low (hypoglycemia). If you forget to take your dose of Humalog, your blood sugar may go too high (hyperglycemia).

Your blood sugar goals

The American Diabetes Association recommends1 blood sugar goals for people with diabetes. These don't apply to everyone, however, so work with your healthcare provider to set the right goals for you.

Before meals (Blood sugar self-check)

80-130 mg/dL

1-2 hours after starting your meal (Blood sugar self-check)

Less than 180 mg/dL

A1C (Tested by your healthcare provider)

Less than 7%

These goals are not applicable to pregnant women or children. These goals should be individualized.

Select Safety Information

Do not take Humalog, Humalog Mix75/25, or Humalog Mix50/50 if your blood sugar is too low (hypoglycemia) or if you are allergic to insulin lispro or any of the ingredients in these insulins.

What is low blood sugar?

Low blood sugar, also called hypoglycemia (usually below 70 mg/dL), is the most common side effect associated with insulins, including Humalog. It can be caused by:

  • Being more physically active than usual
  • Taking too much diabetes medication
  • Eating at the wrong time for the medication you take
  • Taking other medication in addition to Humalog
  • Skipping or not finishing meals or snacks

Low blood sugar can also be caused by a combination of these or other factors.

What does low blood sugar feel like?

  • hungry
  • Hungry
  • tired
  • Tired
  • shaky
  • Shaky
  • sweaty
  • Sweaty
  • irritable
  • Irritable
  • headachy
  • Headachy

Low blood sugar can include one or any combination of these symptoms—and they might not be the same every time, depending on how low your blood sugar gets and which factors caused it to drop. You may even have no symptoms—that's why it's important to test your blood sugar regularly.

Over time, you may learn to recognize the symptoms of low blood sugar and its effects on the body.

Select Safety Information

Low blood sugar (hypoglycemia) is a possible side effect of insulin that may be severe and cause unconsciousness (passing out), seizures, and death. Test your blood sugar levels as your healthcare provider instructs. Talk to your doctor about low blood sugar symptoms and treatment.

Managing low blood sugar

Low blood sugar is very serious, but it usually can be managed. Here are the American Diabetes Association recommendations for what to do immediately if you think you have low blood sugar:

  • Check your blood sugar level. Remember, below 70 mg/dL is usually too low
  • Take something with sugar (see below) right away to quickly raise your level
  • After 15 minutes, check your blood sugar level again
  • Repeat treatment if necessary. If your blood sugar is still low after another 15 minutes, call your emergency service (911) or your healthcare provider

After you have treated your low blood sugar, be sure to eat regular meals and snacks.

How to quickly raise your blood sugar

Three good options for quickly raising low blood sugar levels include:

  • glucose tablets
  • 3-4 glucose tablets
  • jelly beans
  • 15 small, sugary, chewable candies (eg, jelly beans)
  • fruit juice
  • 1/2 cup of fruit juice

Stick to these or similar options. A chocolate bar, for example, has fats and protein that prevent the sugar from being absorbed quickly.

These are guidelines only. These are examples of items that contain 15 grams of carbohydrates. Check food product labels to ensure that you are getting the right amount of carbohydrates. Please discuss recommendations specific to your low blood sugar with your healthcare team.

Low blood sugar is a possible side effect of Humalog that may be severe and cause unconsciousness (passing out), seizures, and death. Test your blood sugar levels as your healthcare provider instructs.

Remember that if low blood sugar is not treated quickly, it can become severe. And severe low blood sugar is very serious.

Glucagon is a treatment for insulin coma or insulin reaction resulting from severe low blood sugar. Glucagon should not be used if you have pheochromocytoma or if you are allergic to Glucagon.

Severe low blood sugar and Glucagon

You'll want to be ready in case you or someone close to you ever experiences severe low blood sugar. If it happens, loss of consciousness may occur. When a person’s blood sugar falls this low, they may be physically unable to eat or drink a fast-acting source of sugar (glucose). They may need a Glucagon shot—and since they’ll be unable to administer it themselves, you, a family member, or another adult will need to be ready to give it to them.

Glucagon is a medicine that’s different from insulin. It works by telling the body to release sugar (glucose) into the bloodstream to bring the blood sugar level back up. The possibility of severe low blood sugar and of giving a Glucagon injection can be scary. But it's very important that you understand how to recognize symptoms of severe low blood sugar, and that you, or other adults around, are ready to give a Glucagon injection, if you have to.

Remember to notify your healthcare provider that an episode of severe low blood sugar (hypoglycemia) has occurred.

Be better prepared to treat severe low blood sugar with a Lilly Glucagon Emergency Kit.

Lilly Glucagon(TM) Emergency Kit

For complete instructions on how to administer Glucagon, please click to access full Information for the User.

Multiple kits, one co-pay

Ask your healthcare provider about prescribing more than one Lilly Glucagon Emergency Kit for severe low blood sugar. That way, you can have one at home, one at school, and one wherever else you may need a kit. Many insurance plans allow you to receive more than one kit with only one co-pay. Check with your insurance provider or your pharmacist to find out how many kits you can get with a single co-pay.

Be better prepared with the Glucagon App

Virtually practice the steps for administering Glucagon, keep track of multiple kits, and get other helpful tips. Get the Glucagon App on iTunes.

To learn more about Glucagon and how it can help you be better prepared, go to

The Glucagon design is a trademark of Eli Lilly and Company. Glucagon is available by prescription only.


  1. American Diabetes Association. Standards of Medical Care in Diabetes—2015. Diabetes Care. 2015;38(suppl 1):S33-S40.