Monitoring Your Blood Sugar


Why do I have to monitor my blood sugar?

Monitoring your blood sugar is the best way to find out how well your diabetes is being controlled, and gives you information on how to manage your diabetes on a daily basis. If your blood sugar is too low or too high, your healthcare provider might want to adjust your diet, exercise schedule, or the amount of medicine you are taking.

Many things, such as food, physical activity, medication and stress, can affect your blood sugar. The following can raise it:

  • Eating too much
  • Not taking your diabetes medication
  • Illness, surgery, or stress
  • Not staying active

These things can lower your blood sugar:

  • Missing meals, or just not eating very much
  • Taking too much diabetes medication
  • Drinking alcohol without eating
  • Too much activity

What should my blood sugar goals be?

Blood sugar goals may be different for each person, and can change throughout the day. The American Diabetes Association recommends these blood sugar goals:

  • Before meals: 80 to 130 mg/dL
  • Two hours after the start of a meal: less than 180 mg/dL
  • Before bedtime: 100-150 mg/dL. If the level is less than 100 mg/dL, have a snack.

What are the symptoms of low blood sugar?

Most people have symptoms of low blood sugar (hypoglycemia) when their blood sugar is less than 70 mg/dL. When your blood sugar is low, your body gives out signs that you need food. Common early symptoms of low blood sugar include the following:

  • Feeling weak
  • Feeling dizzy
  • Feeling hungry
  • Trembling and feeling shaky
  • Sweating
  • Pounding heart
  • Pale skin
  • Feeling frightened or anxious

Late symptoms of low blood sugar include:

  • Feeling confused
  • Headache
  • Feeling cranky
  • Poor coordination
  • Bad dreams or nightmares
  • Being unable keep your mind on one subject
  • Numbness in your mouth and tongue
  • Passing out

Test Details

How do I check my blood sugar?

The usual blood sugar check involves sticking your finger with a small needle called a lancet, putting a drop of blood on a test strip, and using a meter that displays your blood sugar level. Blood sugar meters and test strips are available at your local pharmacy, through mail order, or through your healthcare provider. There are many different types of meters. Your healthcare provider can help you select the meter that is best for you.

If you have insurance, check with your insurance company to see if you are covered. If you do not have insurance, check with your caregiver for other options.

When should I check my blood sugar?

The usual times to check your blood sugar level are before meals and at bedtime. Your healthcare provider will tell you how often and when to check your blood sugar.

How do I check my blood sugar?

Here are the steps for checking your blood sugar:

  1. Gather your supplies.
  2. Wash your hands with soap and warm water. If you are not able to wash with soap and water, use an alcohol wipe. The testing area must be completely dry. Do not use hand sanitizers.
  3. Place a new lancet into the lancing device, following the instructions in the user manual.
  4. Insert a test strip into the meter.
  5. Place the lancing device firmly on the side of your fingertip. Press the button on the lancing device to obtain a drop of blood.
  6. Place the test strip against the drop of blood and allow the strip to absorb it.
  7. Read the result from the meter.
  8. Throw the lancet away in a hard plastic container, according to the guidelines of your local waste disposal agency.

Results and Follow-Up

When should I call my healthcare provider about my blood sugar level?

Proper blood sugar ranges are different for each person and can change throughout the day. Your healthcare provider will tell you what your range should be. Call your healthcare provider if one of the following occurs:

  • Your blood sugar test results are higher than usual (more than 100 mg/dl above your usual results) for more than 2 days for an unknown reason.
  • Your blood sugar level is low (less than 70 mg/dl) more than 2 times a week.

Last reviewed by a Cleveland Clinic medical professional on 09/17/2018.


  • American Diabetes Association. Diabetes Basics. ( Accessed 9/18/2018.
  • The National Institute of Diabetes and Digestive and Kidney Diseases. What is Diabetes? ( Accessed 9/18/2018.
  • American Diabetes Association. A1C and eAG. ( Accessed 9/18/2018.

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