Testing your blood sugar is an important part of managing your diabetes. Knowing your blood glucose levels helps you make decisions about your diabetes management plan.
Blood glucose testing can be done using a portable blood glucose monitor called a glucometer. The test involves pricking your finger to obtain a small blood sample for the glucometer to analyze.
Blood glucose monitoring kits and supplies are available from your doctor or diabetes educator or for purchase at pharmacies and online. Glucose meters come with testing strips, small needles (or lancets) to prick your finger, and a device to hold the needle. They may come with either a logbook in which you can record your blood glucose results or ways to automatically download the readings into your computer.
Meters vary in cost and size, and they may come with different special features to suit different needs, including:
- audio capabilities for people with vision impairments
- backlit screens to aid visibility in low light
- additional memory or data storage
- different handling capabilities, such as having the strips store in the meter, or having a USB meter
Blood glucose monitoring can help you manage your diabetes and can help you make important decisions about your medication dosage, exercise, and diet. Monitoring can help you identify when your blood sugar is too high or too low.
Your doctor will calculate the target range for your blood glucose based on your age, your type of diabetes, your overall health, and other factors. It is important to keep your glucose levels within your target range because high blood sugar levels, if untreated, can lead to the chronic complications sometimes seen with diabetes, such as heart disease, nerve damage, and kidney disease.
Low blood sugar levels, on the other hand, can cause a variety of symptoms from mild to moderate confusion and weakness to serious acute complications such as coma.
For people with type 1 diabetes, testing may be required three or more times a day. This includes before and after meals and exercise, and more often when you are sick.
For people with type 2 diabetes, when and how often to test will be defined by your doctor or health care professional.
Regular glucose monitoring can help people with diabetes learn more about their condition and how their blood glucose levels are affected by activities and conditions, including diet, exercise, illness, and stress.
Blood glucose monitoring can also help to alert you if your blood glucose levels become dangerously high or low.
There is a risk of spreading blood-borne illness if you share insulin needles and testing supplies with someone else. You should never share needles or finger-stick devices for any reason.
Risks from the blood glucose test, which are minimal, are substantially lower than the risk of not monitoring your blood sugar levels.
Before checking your blood glucose levels, make sure that you have all the necessary equipment:
- finger-stick device to prick your finger
- alcohol swab to sterilize the puncture site
- blood glucose monitor
Also, depending on the type of test you are taking, you may need to adjust your meal schedule. Your doctor may recommend taking a test after fasting for a time.
Before you begin, wash your hands thoroughly to prevent infection at the finger-prick site. If you use alcohol wipes instead of washing, be sure to let the site dry completely before testing.
Then put a testing strip into the meter. Prick your finger with the lancet to get a small drop of blood. Use the sides of the fingertips instead of the tip itself to decrease finger discomfort.
You will apply the blood to a special test strip that you’ve inserted into the meter. Your monitor will give you your blood glucose reading on its digital display.
Finger pricks rarely require a bandage, but you may want to use one if bleeding continues beyond a few drops. It’s important to follow all the instructions that came with your glucometer to ensure accurate results.
The American Association of Clinical Endocrinologists recommends fasting and pre-meal glucose values of less than 110 mg/dL, and two-hour post meal values under 140 mg/dL.
Talk to your healthcare provider about your target levels.
Regular blood glucose monitoring can help you identify fluctuations in your blood sugar levels so you can learn how food, exercise, stress, and other factors affect your diabetes.