VDRL test

Definition

The VDRL test is a screening test for syphilis. It measures substances (proteins), called antibodies, which your body may produce if you have been infected with the bacteria that cause syphilis.

Alternative Names

Venereal disease research laboratory test; Syphilis - VDRL

How the Test is Performed

The test is most often done using a blood sample. It can also be done using a sample of spinal fluid. This article discusses the blood test.

A blood sample is needed.

How the Test will Feel

When the needle is inserted to draw blood, some people may feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.

Why the Test is Performed

This test is similar to the rapid plasma reagin (RPR) test. It is used to screen for syphilis. The bacteria that cause syphilis is called Treponema pallidum.

Your health care provider may order this test if you have signs and symptoms of a sexually transmitted illness (STI) or certain other symptoms.

Syphilis screening is a routine part of prenatal care during pregnancy.

The test is also used to monitor the progress of the treatment for syphilis. After treatment with antibiotics, the levels of syphilis antibodies should fall. Unchanged or rising levels can mean a persistent infection.

Normal Results

A negative test is normal. It means that no antibodies to syphilis have been seen in your blood sample.

The screening test is most likely to be positive in the secondary and latent stages of syphilis. This test may give a false-negative result during early- and late-stage syphilis. This test must be confirmed with another blood test to make the diagnosis of syphilis.

Normal value ranges may vary slightly among different labs. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test results.

What Abnormal Results Mean

A positive test result means you may have syphilis. If the test is positive, the next step is to confirm the results with an FTA-ABS test, which is a more specific syphilis test.

The VDRL test's ability to detect syphilis depends on the stage of the disease. The test's sensitivity to detect syphilis nears 100% during the secondary and latent stages; it is less sensitive during the earlier and later stages.

Some conditions may cause a false-positive VDRL test, including:

The body does not always produce antibodies specifically in response to the syphilis bacteria, so this test is not always accurate.

Risks

There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

References

Radolf JD, Salazar JC. Syphilis (Treponema pallidum). In: Blaser MJ, Cohen JI, Holland SM, et al, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 10th ed. Philadelphia, PA: Elsevier; 2026:chap 243.

US Preventive Services Task Force; Mangione CM, Barry MJ, et al. Screening for syphilis infection in nonpregnant adolescents and adults: US Preventive Services Task Force Reaffirmation Recommendation Statement. JAMA. 2022;328(12):1243-1249. PMID: 36166020 pubmed.ncbi.nlm.nih.gov/36166020/.



Review Date: 8/5/2025
Reviewed By: Jatin M. Vyas, MD, PhD, Roy and Diana Vagelos Professor in Medicine, Columbia University Vagelos College of Physicians and Surgeons, Division of Infectious Diseases, Department of Medicine, New York, NY. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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