Common Blood Glucose Monitoring Mistakes

Blood glucose meters are reliable when used properly, but they depend on the person using them. Small slips in technique can shift a result enough to mislead you. These are the mistakes that healthcare professionals see most often, with simple ways to fix them.

Mistakes before the test

1. Not washing your hands

Traces of fruit, juice or lotion on the fingertip can raise a reading significantly. Wash with soap and warm water and dry thoroughly before every test.

2. Testing with wet hands

Water or leftover alcohol can dilute the blood drop. Dry completely.

3. Using expired or badly stored strips

Heat, humidity and age degrade strips. Keep them in their closed vial and check the date.

4. Using the wrong strips

Strips are designed for a specific meter. Using a different brand, or pre-owned strips of unknown history, risks wrong results. The FDA warns against previously owned strips.

Mistakes during the test

5. Too little blood

An insufficient sample can cause an error or a falsely low reading. Let a full drop form before touching the strip to it.

6. Squeezing the finger hard

Forceful squeezing can mix tissue fluid with the blood. Gently massage from the base of the finger instead.

7. Pricking the pad of the finger

The center of the fingertip has more nerve endings. Use the sides and rotate fingers.

8. Reusing lancets

A used lancet is blunt and no longer sterile. Use a new one every time, such as our Sterile Lancets 30G.

Mistakes after the test

9. Not recording results

A reading you do not record cannot reveal a pattern. Use a logbook, the meter’s memory or an app, and note meals, activity and medicines.

10. Reacting to a single reading

One unexpected number may be an error. Wash your hands, retest with a new strip, and look at the trend over days. Do not adjust medicines unless your team has taught you how.

Equipment mistakes

• Ignoring the meter’s settings: check that the date, time and units are correct so stored results make sense.
• Skipping control solution tests: run one when you open new strips or doubt a result.
• Not cleaning the meter: dried blood or dust can interfere with readings.
• Testing in extreme conditions: very hot or cold temperatures and high altitude can affect results. Let the meter return to room temperature.

Safety mistakes

• Sharing equipment: lancing devices and lancets must never be shared; doing so can spread blood-borne infections.
• Throwing sharps in the trash: used lancets belong in a sharps container, such as our Sharps Disposal Container.
• Leaving supplies within reach of children.

Planning mistakes

• Testing at random times: follow the schedule your team recommends so results are comparable.
• Running out of strips: reorder early.
• Not taking the meter to appointments: your team can check your technique and compare the meter with a laboratory test.

Alternative-site caution

Results from the forearm or palm can lag behind fingertip results when glucose is changing rapidly. Use the fingertip after meals, after exercise and whenever you suspect a low.

When readings and symptoms disagree

If you feel unwell but the number looks normal, or the number looks alarming but you feel fine:

1. wash your hands and repeat the test;
2. check the strips and run a control test;
3. treat symptoms of low blood sugar as your team has advised;
4. contact your healthcare team if the discrepancy continues.

The bottom line

Clean, dry hands; fresh, correct strips; enough blood; a new lancet; and a written record. Getting these basics right gives you numbers worth acting on. Find testing supplies in our diabetes care department.

Sources

1. U.S. Food and Drug Administration. Blood Glucose Monitoring Devices.
2. Centers for Disease Control and Prevention. Monitoring Your Blood Sugar.
3. American Diabetes Association. Check Your Blood Glucose.
4. U.S. Food and Drug Administration. Safely Using Sharps (Needles and Syringes) at Home, at Work and on Travel.