Blood Glucose

Alternate Site Testing

January 11, 2017   /
Elaine M. Hinzey, RD, LDN

The term alternate site testing refers to the use of body parts other than the fingertips to test your blood glucose level. The fingertips have a lot of nerve endings, which increases the pain perception when they are pricked. This is especially problematic for people who use their hands frequently. Other body parts, such as the forearm, have fewer nerve endings per square inch.

Common body parts used for alternate site testing include the:

  • Forearms
  • Thighs
  • Calves
  • Upper arms
  • Palms

Vaculance® lancets are used for alternate site testing. These create a vacuum to bring blood to the surface. You can use them with the most painless glucose monitors, but not on the fingertips. Using the clear cap on the lancet device allows you to see when you have adequate blood flow. You should hold the lancing device on the skin for 5 seconds to allow adequate blood flow. It is recommended that you vigorously rub alternate sites before testing to increase blood flow to the area.

Follow these recommendations:

  • Check to make sure you can use your blood glucose meter for alternate site readings—not all meters are designed for this
  • Realize that blood flow to the fingertips occurs three to five times as rapidly as it does to other parts of the body, so if your blood glucose level is changing rapidly, use your fingertips for testing
  • Use your fingertip if you test sooner than 2 hours after a meal, an insulin dose, or exercise
  • Understand that the forearm and finger results usually are within 20% of each other for fasting blood glucoses or those taken 2 hours or more after a meal
  • Know that you are not a good candidate for alternate site testing if you frequently become hypoglycemic or have hypoglycemia unawareness
  • Avoid testing in areas with body hair, which can cause the blood to smear and interfere with the test
  • Choose an area for testing that is free of obvious veins


References and recommended readings

Abbott. Alternative site testing. Accessed August 27, 2012.

American Diabetes Services. Alternate-site testing. Accessed August 27, 2012.

Diabetes Care Club®. Alternate site testing. Accessed August 27, 2012.