Antibiotic Titers (Serum/Plasma) – Quantitative Measurement

Why This Test Is Done

Your healthcare provider may order this test if you’re being treated for an infection caused by bacteria that are sensitive to certain antibiotics. It helps ensure the right antibiotic is used at the correct dose and duration. This is especially important for infections like bloodstream infections, urinary tract infections, or severe bacterial illnesses.

How the Test Works

A small blood sample is taken, and the antibiotic(s) in your serum or plasma are measured using a sensitive laboratory method, such as immunoassay or nephelometry. The test quantifies the concentration of the antibiotic to assess its effectiveness.

What to Expect Before the Test

No special preparation is needed for this test. You may have a slight bruise or discomfort at the injection site, but it usually goes away quickly. If you’re on blood thinners, let your doctor know before the test.

What to Expect After the Test

After the blood draw, you can return to your normal activities. If you experience excessive bleeding or unusual pain, contact your healthcare provider. Most people don’t need follow-up care unless their results are abnormal.