How long does STI screening take to work for syphilis?

Blood tests look for antibodies made in response to Treponema pallidum, the bacterium that causes syphilis. Those antibodies may not be detectable during the earliest stage. A test taken soon after sexual contact can therefore be negative even when infection is developing. The clinician may recommend a repeat test after an interval based on the exposure, symptoms, and test used. A swab or other sample may be considered when a sore is present, while blood testing is commonly used for broader assessment.

Tell the clinician when the possible exposure occurred, whether you used protection, and whether you have a painless sore, rash, swollen glands, or other new symptoms. Avoid sexual contact or use condoms until you have received advice about transmission and testing. Do not rely on a single early negative result if the exposure was recent. Partners may also need assessment, and treatment should be taken exactly as prescribed if syphilis is diagnosed.

Arrange medical assessment promptly after a known exposure, a new genital or mouth sore, an unexplained rash involving the palms or soles, or swollen glands. Seek urgent care for eye pain or vision changes, hearing changes, severe headache, confusion, weakness, or difficulty walking, because syphilis can affect the nervous system or sensory organs. If you are pregnant or could be pregnant, contact a clinician quickly after a possible exposure.

Ask which syphilis test is being used, whether the timing of your test fits the exposure date, and when repeat testing would be useful. You can also ask whether other STI tests, partner notification, or treatment is appropriate.