• Traditional Home Blood Sugar Monitoring. The traditional method of testing your blood sugar involves pricking your finger with a lancet (a small, sharp needle), putting a drop of blood on a test strip and then placing the strip into a meter that displays your blood sugar level. Meters vary in features, readability (with larger displays or spoken instructions for the visually impaired), portability, speed, size, and cost. Current devices provide results in less than 15 seconds and can store this information for future use. These meters can also calculate an average blood sugar level over a period of time. Some meters also feature software kits that retrieve information from the meter and display graphs and charts of your past test results. Blood sugar meters and strips are available at your local pharmacy.
  
  
• Meters That Test Alternative Sites. Newer meters allow you to test sites other than your fingertip; these alternative testing sites include upper arm, forearm, base of the thumb, and thigh. However, testing at alternative sites may give you results that are different from the blood sugar levels obtained from the fingertip. Blood sugar levels in the fingertips show changes more quickly than those in alternative testing sites. This is especially true when your blood sugar is rapidly changing, like after a meal or after exercise. It is also important to know that if you are checking your sugar at an alternative site while you are experiencing symptoms of hypoglycemia, you should not rely on these test results.
  
  
• Lasers to draw blood. In 1998, a laser to draw blood was approved by the U.S. Food and Drug Administration (FDA). The laser device produces a precise beam of light that penetrates the skin on the finger instead of pricking it, reducing pain and discomfort.
  
  
• MiniMed Continuous Glucose Monitoring System. This device involves a small plastic catheter (very small tube) that is inserted just under the skin. It collects small amounts of fluid and measures the sugar content over 72 hours.
  
  
• GlucoWatch. In 2001, the FDA approved the GlucoWatch, a watch-like device that helps people with diabetes measure their blood sugar via tiny electric currents. It draws small amounts of fluid from the skin and measures blood sugar levels three times per hour for up to 12 hours. The GlucoWatch is considered a first step toward noninvasive, continuous sugar monitoring, but it does have some shortfalls.

According to the FDA, these newer devices should not replace the traditional daily finger pricks.

When Should I Test My Blood Sugar?

Blood sugar testing is usually recommended before meals, after meals, and at bedtime. Daily blood sugar checks are especially important for people on insulin or the sulfonylureas class of antidiabetes drugs.

Frequency and timing of blood sugar measurements should be individualized. Your health care provider will tell you when and how often you should check your blood sugar.

Note: Acute or chronic illnesses or changes in medications may affect your blood sugar level. You may need to test your blood sugar more frequently when you are ill.

Conditions That Affect Your Blood Sugar

Certain conditions may interfere with an accurate reading of blood sugar and include:

• Anemia
• Gout
• High air temperature
• Humidity
• Altitude

If you are consistently seeing abnormal results, recalibrate your meter and check the strips.

The chart below gives you an idea of where your blood sugar level should be throughout the day. Your ideal blood sugar range may be different from another person's and will change throughout the day.

Home Blood Glucose Monitoring and HbA1c

Monitoring your HbA1c level is also important for diabetes control. Many home glucose monitors have the capacity to display an average blood glucose reading, which correlates with the HbA1c.

Learn more about HbA1c.

When Should I Call My Doctor About my Blood Sugar?

In most cases, a fasting blood sugar level more than 180 mg/dL is too high and a blood sugar level less than 70 mg/dL is too low. If you are having symptoms of low blood sugar, or if your blood sugar is less than 70 mg/dL and you have more than one unexplained low blood sugar reaction a week, call your health care provider.

If you are having symptoms of high blood sugar, or if your blood sugar is greater than 180 mg/dL for more than a week, or if you have two consecutive readings greater than 300 mg/dL, call your health care provider. In most cases, your doctor will suggest changes in your diabetes management plan.

How Do I Record My Blood Sugar Test Results?