Home blood sugar testing

Check your blood sugar levels often, and write down the results. This will tell you how well you are managing your diabetes.

Not everyone with diabetes needs to check their blood sugar every day. But some people may need to check it many times a day.

Check Your Blood Sugar Often

Usual times to test your blood sugar are before meals and at bedtime. Ask your doctor how often you should check your blood sugar.

Other times to check your blood sugar may be:

  • After you eat out, especially if you have eaten foods you do not normally eat
  • If you feel sick
  • Before or after you exercise
  • If you have a lot of stress
  • If you eat too much, or skip meals or snacks
  • If you are taking new medicines, took too much insulin or diabetes medicine by mistake, or took your medicine at the wrong time
  • If your blood sugar has been higher or lower than normal
  • If you are drinking alcohol

How to Prepare for the Test

Have all test items within reach before starting. Timing is important. Clean the needle prick area with soap and water. Completely dry the skin before pricking.

How the Test is Done

Most glucose meters have test strips, small needles that fit into a spring-loaded plastic device, and a logbook for recording your numbers. There are many different kinds of meters. But they all work much the same way.

You can buy a testing kit from a pharmacy without a prescription. Your doctor or nurse can help you choose what’s right for you. They can also help you set it up and teach you how to use it.

You will prick your finger with the needle and place a drop of blood on a special strip. This strip measures how much glucose is in your blood. (Newer monitors can use blood from other areas of the body besides the fingers, reducing discomfort.) The meter shows your blood sugar results as a number on a digital display.

Keep a Record

Keep a record for yourself and your health care provider. This will be a big help if you are having problems controlling your diabetes. It will also tell you what you did when you were able to control your diabetes. To get the most help with controlling your blood sugar, write down:

  • The time of day
  • Your blood sugar level
  • The amount of carbohydrates you ate
  • The type and dose of your diabetes medicine
  • The type of any exercise you do and how long you exercise for
  • Anything unusual, such as stress, eating different foods, or being sick

Most types of blood sugar meters can store hundreds of readings. This makes it easy to look back at your record and see where you may have had problems.

Saving your blood sugar information to your computer is an easier way to spot problems. Most meters:

  • Are able to save their readings to a computer. Buy one that will work with your computer.
  • Can give you a report of how your blood sugar readings have been

You and your doctor should set a target goal for your blood sugar levels for different times during the day. If your blood sugar is higher than your goals for 3 straight days and you do not know why, call your doctor or nurse.


American Diabetes Association. Standards of medical care in diabetes -- 2010. Diabetes Care. 2010 Jan;33 Suppl 1:S11-61.

Update Date: 11/11/2012

Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.


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