What Is A Globulin Test?

A test measuring protein in the blood

A globulin test (globulin electrophoresis), is a blood test that measures levels of a group of proteins called globulins. There are four types of globulin proteins: Alpha 1, Alpha 2, beta, and gamma globulin proteins. Globulins make up a little less than half of the proteins in the blood.

These proteins have several functions, including immune defense, transporting substances, and enzymatic processes.

Two subtypes of the globulin test can be used to test for these proteins: a total protein test or a serum protein electrophoresis test.

Phlebotomist preparing to do a blood draw on a patient
Simon's Photo / Getty Images

Purpose of Test

A globulin test is a blood test. It is performed by a healthcare professional who takes a sample of blood from your arm.

If your doctor orders a total protein test, they want to measure the amount of Alpha 1, Alpha 2, and beta globulin proteins in your blood. They will also check albumin levels (a liver protein), as measuring total protein is part of liver function tests.

If you have symptoms such as yellow skin (jaundice), nausea, vomiting, itching, constant fatigue, swelling or fluid buildup (edema), and loss of appetite, your doctor may order tests to see how your liver is working.

Globulin proteins are important to liver and kidney function. A total protein test is a good indication of how the liver is working. Low total protein levels can be a sign of liver disease.

The second type of globulin test is serum protein electrophoresis. This test measures gamma globulin and other trace proteins in the blood. Gamma globulins contain antibodies that help the body attack foreign substances and fight disease.

Antibodies are important for maintaining a healthy immune system. Tests that measure gamma globulin can be used to diagnose hyperactive immune system issues including allergies and autoimmune disorders.

An increase in gamma globulin proteins can indicate infection, chronic inflammation, and in severe cases, a type of cancer called multiple myeloma.

While these tests can help a doctor make a diagnosis, a doctor will also use other tests and evaluations to diagnose a specific condition or illness.

Globulin tests can help diagnose liver disease, kidney disease, malnutrition or malabsorption, immune system disorders, and some forms of cancer.

If your doctor suspects one of these conditions or is specifically concerned about your liver or kidney function, they may order globulin tests right away.

However, they will still do a physical exam, take your medical history, and may need to order other tests to confirm a diagnosis.

Risks and Contraindications

Globulin tests require a blood sample. A blood draw (venipuncture) is a routine procedure that can be completed at a doctor's office, clinic, or outpatient lab.

Most people don't experience any problems during or after a blood draw. However, when a vein is punctured it's possible the following can occur:

  • Broken blood vessels under the skin (hematoma)
  • Dizziness or lightheadedness
  • Excessive bleeding
  • Infection resulting from skin puncture

While they do not typically occur, these outcomes can be addressed immediately and generally do not have longterm medical consequences.

For healthy people, the overall risk associated with venipuncture is low. The technicians who perform blood draws take steps to lower the risk, such as using single-use needles and appropriate safety precautions.

In most cases, the benefits of the test outweigh the risk associated with having blood taken. However, there are cases where a person should not have a blood draw (contraindication). For example, if they have a skin infection (cellulitis) in the area.

Before the Test

You may be required to not have anything to eat or drink (fast) for several hours or overnight before taking a globulin test. Your doctor will let you know if you need to fast and for how long.

Certain medications can affect the results of the test. Let your doctor know if you take any of the following medications.

Do not skip or change your medication dose unless your doctor tells you to. If the test will be affected, they may have you take your normal dose at a different time.

Your doctor will take your medical history, review your list of medications, complete a physical examination, and ask questions about your family health history before ordering a globulin test. This information, plus the test results, will help them arrive at a diagnosis.

Most blood draws can be done in-office on the same day your doctor decides to complete the test. However, if you have to fast before the test, it will need to be scheduled for a later date.

Timing

Having blood taken for a globulin test usually only takes a few minutes. However, there are other steps you'll need to complete which can add to the overall time you'll spend on the task.

For example, if you are going to the outpatient lab at a clinic or hospital, you may need to register and provide a copy of the lab order (requisition) from your doctor.

The patient registration staff may ask you to confirm that information on file for you, such as your health insurance and emergency contacts, is current.

Before taking your blood, the technician will ask you to verify your name and date of birth to ensure the vials of blood are appropriately labeled.

Your medical records are confidential, and providing this information is a standard part of health information security.

Once your blood sample has been taken, you can go home. Your doctor will contact you when the results of the test come back.

Location

Some doctor's offices can perform blood draws for a globulin test on-site, which means you may give a blood sample the same day your doctor orders the test.

However, most physician’s offices require patients to have their blood drawn at an external laboratory they contract with. These laboratories are large companies with many locations, including in hospitals or clinics.

When you arrive at the testing facility, you will check-in at the front desk. Your doctor will have given you registration paperwork to give to the receptionist. These papers let the technician know which tests you are having so they can take the appropriate amount of blood.

After you are checked in and the technician has reviewed your doctor's orders, you will be taken to an individual exam room or a specific area of the lab that is set up for blood taking procedures (phlebotomy).

What to Wear

You do not have to remove your clothing or change into a gown to have blood drawn. However, the person taking your blood needs to access the vein in your arm at the crease of your elbow. Wearing layers or a top with sleeves that are easy to push up can be helpful.

Food and Drink

Your doctor may tell you to fast before the test. This means you will need to avoid having anything to eat or drink for a certain period of time before having your blood taken.

Your doctor will tell you how long you need to fast, but it's often at least four hours prior to the test or the night before the test.

If you take certain medications, your doctor might have you stop taking them before the test. Don't stop taking your medications unless your doctor tells you to.

If you will be allowed to keep taking your medications during your fast, you may be able to have a small sip of water to take them with.

It's a good idea to drink extra water the day before your blood draw. When you're properly hydrated, your veins are larger and allow for easier access. Dehydration can make it more difficult for a blood sample to be taken and may increase the risk of complications.

Cost and Health Insurance

Having blood drawn for a globulin test is a routine procedure and should not require pre-approval by your insurance. The cost of a specific lab test will vary from one lab and one insurance plan to the next, but most routine blood draws are covered.

Contact your insurance provider before the test to find out how much, if any, out-of-pocket cost there will be.

What to Bring

If your doctor has given you paperwork about your test to give to the registration clerk or lab employee, you will need to bring it with you on the day of your blood drawn. In some healthcare systems, the paperwork may be faxed or delivered electronically.

The lab needs to have this paperwork, either from you or your doctor's office directly, to complete the test.

You should also bring your health insurance cards and photo identification, as you may be asked to show it when you register.

You may have to wait for registration or when you get to the lab. You might want to bring a magazine or a book. There are often reading materials in the waiting area as well.

During the Test

While your doctor will order the test, a healthcare professional called a phlebotomist will take the sample of your blood. Phlebotomists are specially trained and certified to complete blood draws.

Pre-Test

If you are at your doctor’s office, you will need to complete the same paperwork you do for any visit. This can include showing your insurance cards, filling out a basic demographics form, and confirming your contact information is correct.

If your doctor sends you to another part of their office to complete the blood draw, you will likely need to bring a registration form with you. This paper provides details of the test and lets the phlebotomist know how much blood needs to be drawn.

The information about you that is included in the paperwork (like your name and date of birth) ensures the sample of blood is appropriately labeled and doesn't get lost or mixed up when it is sent off to be tested.

Throughout the Test

You will be seated during a blood draw, either in a regular chair or a special chair at the lab. The phlebotomist will look at your veins to determine the best one to draw from or may ask you if you have a preference as to which arm they draw from.

Next, the phlebotomist will tie a band around the upper part of your arm to temporarily stop the blood flow. This allows them to see your veins better. If you have prominent, readily visible veins, the phlebotomist may not need to perform this step.

Then, the phlebotomist will use an antibacterial wipe to sterilize the inside crease of your elbow. They may use a sterile marker to mark the area over the vein where the needle will go.

Some people experience a slight stinging or pinching sensation as the needle is inserted. The discomfort is typically mild and doesn't last long.

When you are adequately hydrated, the process usually only takes a few minutes. If the blood is not flowing well, the phlebotomist may ask you to squeeze a small ball to help.

Let the phlebotomist know if you become dizzy, lightheaded, or feel like you're going to faint during or after having your blood drawn.

Post-Test

The area where the vein was punctured will be covered with a cotton pad and medical tape. The phlebotomist may instruct you to keep these on for the next several hours.

It's usually recommended that you refrain from heavy lifting, exercise, or strenuous activity for several hours after the blood draw.

Blood draws do not typically have an extended recovery period, so you will be able to drive yourself home after the test. If you become dizzy or faint, you will be asked to stay at the lab for a little while to rest, have a snack, and something to drink.

After the Test

There are no special instructions to follow after a blood draw for a globulin test. Your doctor may let you know when to expect the results. They will contact you when the test comes back and may ask you to return to the office to go over the results.

You shouldn't have any major longterm issues related to having your blood taken. Even if you got dizzy or fainted after the test, healthy people usually recover quickly with rest and fluids.

Fainting after having your blood drawn is commonly due to dehydration or low blood sugar (hypoglycemia), especially if you were fasting before the test.

Interpreting Results

Results usually take several days to one week to arrive, depending on the size of the laboratory. Your doctor will receive the results, interpret them, determine what the next steps will be, then relay all of this information to you.

Results from a globulin test come in the form of laboratory values. These numbers indicate whether a person has healthy levels of proteins in their blood.

Protein globulin levels for adults normally fall between 2.3 and 3.4 grams per deciliter (g/dL). The normal range for total protein is between 6.4 and 8.3 g/dL.

In some cases, these proteins may be elevated. For example, it's normal for these proteins to be higher during pregnancy.

A total protein test also provides the albumin to globulin ratio (A/G ratio). The 1:1 ratio responds to how much of each component there is in the blood (for example, if albumin levels are higher than globulin levels). In general, a value of just above 1 is considered normal.

A low ratio can be a sign of autoimmune disorders, poor kidney function, or liver disease. A high ratio may indicate certain types of cancer or genetic conditions.

The results of a globulin test are not used alone. Your doctor will interpret them with the findings from your physical examination, medical history, and other tests before making a diagnosis.

Follow-Up

If the results are normal, you won't need any specific follow-up for the test. However, your doctor may want to run other types of tests if you are having symptoms.

If the results are outside the normal range, your doctor may have you do additional blood tests to provide more specific information. If your doctor suspects a specific condition like cancer, you may need imaging tests like an MRI to look for tumors or swollen lymph nodes.

A Word From Verywell

Any medical procedure can tax a person’s emotional and physical health. A blood draw for a globulin test is generally safe for most people, doesn't take a lot of time, and will usually be covered by a health insurance plan. However, you should still understand the procedure and its risks.

When the results of the test come back, you will want to talk to your doctor about any additional tests that are needed as well as what your treatment options are.

There are steps you can take to improve your health even before the test is done and regardless of what the results are.

Eating a balanced diet, exercising, losing weight if needed, and quitting smoking can all improve your overall health. If you're anxious about the test, the results, or what comes next, stress management and relaxation techniques can help.

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Article Sources
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