There is no special preparation for a glycohemoglobin test. The blood sample can be taken anytime, without the fasting that some glucose tests require.

When the test is performed in a physician’s office for laboratory analysis, blood is usually drawn from a vein (venipuncture) from the inside of the elbow or the back of the hand. First the puncture site is sterilized with antiseptic and an elastic band is wrapped around the patient’s upper arm. As a result, the pressure restricts blood flow through the vein and causes the veins below the band to fill with blood.

A needle is then inserted into a vein. Occasionally more than one puncture is necessary to locate a vein. Some people may feel a moderate level of pain when the needle is inserted, but most only feel a prick or stinging sensation. Once the needle is inserted into a vein, a tube is attached to collect the blood as it begins to flow out. The elastic band is then removed.

After the necessary amount of blood is collected, the needle is withdrawn and a small cotton ball or pad is applied with light pressure over the puncture site. After several minutes, the cotton will be discarded or replaced, and a small bandage will be placed on the puncture wound. The entire process takes less than 10 minutes. The sample is sent to a laboratory for analysis, and results are returned in several days.

Despite the precautions taken to avoid bruising and soreness, it does sometimes occur. Typically, this is not a cause for concern. To minimize soreness, patients may immediately apply a warm compress to the puncture site and repeat the application every three hours until the discoloration or pain subsides.

Glycohemoglobin tests performed in a physician’s office or at home do not require a venipuncture, but rather drops of blood from a finger prick. Some home tests require the user to mail a blood sample to a lab for analysis. With this test the patient uses a lancet provided in the kit to produce a couple of drops of blood. The patient than places the blood on a special collection card and mails the card to the company’s lab for analysis. The results are then returned to the user.

Some tests provide immediate results to the patient and physician. A physician can collect a drop of blood from a finger prick into a supplied capillary holder. Light pressure and sterile gauze are then applied to the puncture site to stop the bleeding. A bandage is usually not necessary. The sample is then inserted into a cartridge, and the cartridge is placed in an analyzer. Results are available in 15 minutes. The patient can then discuss the results with the physician.

At least one over-the-counter home test provides results in less than 10 minutes. The test requires the user to prick a finger and collect drops of blood into a provided pipette. The patient then dilutes the sample by placing it in a provided test solution and mixing it. The diluted sample is then applied to the provided monitor. Light pressure and sterile gauze are applied to the puncture site to stop the bleeding. A bandage is usually not necessary. Results are available in eight minutes. Some glucose meters also offer glycosylated hemoglobin testing.

Home tests should not replace testing by the physician. Patients performing home tests should always discuss results with their physician.

After the test, the patient may feel some throbbing. There is a slight risk of infection at the puncture site.