This page is general health information, not medical advice. It cannot tell you whether you have an infection. A clinician can, and the testing options on this site are a good place to start.

Syphilis is a bacterial infection that has been known for centuries. It is also one of the most treatable infections in sexual health care.

The hard part is that it can be quiet. A sore may be painless and out of sight. A rash may look like many other skin conditions. Then both can fade without treatment while the infection stays in the body.

This guide walks through the science in plain words. It covers the organism that causes syphilis, the stages, the blood tests, and the treatment a clinician prescribes. It also covers what Louisiana's numbers look like and where free or low-cost testing is available in Baton Rouge.

It is general education. Only a clinician and a lab test can tell a person what is going on in their own body.

The short version

Syphilis is caused by a bacterium. Yes, syphilis is curable. The CDC STI Treatment Guidelines (2021) name penicillin, prescribed by a clinician, as the preferred treatment.
Syphilis symptoms come in stages and can be mild or unnoticed. Testing is how people find out.
Diagnosis uses two kinds of blood tests, usually together.
Follow-up blood tests after treatment help a clinician see whether the treatment is working.
The CDC's 2023 surveillance report ranked Louisiana 8th among the states for primary and secondary syphilis.

What causes syphilis: the organism and the medicine

The prompt for this section is usually "what is in it." For an infection, the useful answer is two things: the organism and the drug class used against it.

The organism

Syphilis is caused by Treponema pallidum, a thin, spiral-shaped bacterium called a spirochete. According to the CDC, it spreads through direct contact with a syphilis sore during vaginal, anal or oral sex. It can also pass from a pregnant person to a baby.

Research suggests this bacterium is hard to grow in a routine laboratory dish. That is one reason diagnosis relies mostly on blood tests that look for the body's response, rather than on growing the organism.

The medicine class

Penicillin belongs to the beta-lactam family of antibiotics. Research on how these drugs work suggests they interfere with the way bacteria build their outer wall, which weakens and kills them.

The CDC STI Treatment Guidelines (2021) report that T. pallidum has stayed sensitive to penicillin. That is why it remains the first choice decades after it was introduced. The same guidelines note that some other antibiotics are not relied on in the same way, so the choice of medicine belongs to a clinician.

Syphilis symptoms by stage

The CDC describes syphilis in stages. The stages can overlap, and some people never notice any of them.

Primary stage: a sore

The first sign is usually a single sore called a chancre. It tends to be firm, round and painless. It appears where the bacteria entered the body, which may be on the genitals, in the rectum or in the mouth.

Because it does not hurt and can be inside the body, it is easy to miss. The CDC says the sore heals on its own in a few weeks, even without treatment. Healing does not mean the infection is gone.

Secondary stage: the syphilis rash and other signs

The secondary stage often brings a rash. The CDC describes the syphilis rash as varied. It may look rough, red or reddish-brown, and it often appears on the palms of the hands and the soles of the feet. It usually does not itch.

It can also show up on the chest, back or other areas, and it can be faint enough to overlook. Other possible signs listed by the CDC include:

Fever and tiredness
Sore throat
Swollen lymph nodes
Patchy hair loss
Muscle aches and headaches
Wart-like or moist patches in warm areas of the body

A rash by itself cannot show whether someone has syphilis. Many skin conditions look alike. A clinician and a blood test can sort it out.

Latent stage: no signs at all

After the secondary stage, the CDC says signs can disappear and the infection can stay in the body without symptoms. This is called latent syphilis. A blood test is the main way it is found.

Tertiary stage and other serious effects

The CDC says that, without treatment, syphilis can eventually damage organs such as the heart, blood vessels, brain and nerves. This stage is uncommon, and it can appear years after infection.

Syphilis can also reach the eyes, ears or nervous system at any stage. These are called ocular syphilis, otosyphilis and neurosyphilis. Vision changes, hearing changes, severe headaches or confusion are reasons to be seen promptly by a clinician.

Why the national rise matters

The CDC has reported increases in syphilis across the United States in recent years, including among women and newborns. Congenital syphilis, which happens when the infection passes to a baby during pregnancy, is one of the reasons public health agencies pay close attention.

The reason it matters to an individual is simple. More infection in a community means more chances for it to pass unnoticed. Regular testing and quick treatment are how communities slow that down.

The CDC's 2024 guidance on doxycycline post-exposure prophylaxis (doxy-PEP) is part of that response. Research the CDC reviewed suggests that, in trials, taking doxycycline after sex was linked to fewer syphilis, chlamydia and gonorrhea infections among certain groups. The CDC's recommendation is for gay, bisexual and other men who have sex with men, and transgender women, who had a bacterial STI in the past year. It is something to discuss with a clinician, who decides whether it fits and prescribes it.

Syphilis in Baton Rouge and Louisiana

City-level syphilis numbers for Baton Rouge were not available to this writer. For exact local figures, the Louisiana Department of Health is the place to ask.

State-level numbers are published. According to CDC STI Surveillance 2023, Louisiana reported 1,196 cases of primary and secondary syphilis, a rate of 26.1 per 100,000 people. That ranked Louisiana 8th among the states.

The same CDC report ranked Louisiana 1st for chlamydia (792.4 per 100,000) and 2nd for gonorrhea (288.4 per 100,000). These infections often occur together, so a clinician may offer tests for several at once.

These numbers describe a state, not any one person. They do not mean any individual is likely to have an infection. They do help explain why local clinics treat routine testing as ordinary health care.

How syphilis testing works

Syphilis is diagnosed mainly with blood tests. Sometimes a clinician also takes a swab from a sore. The CDC STI Treatment Guidelines (2021) describe two types of blood test.

Treponemal tests

These look for antibodies that the body makes against the syphilis bacterium itself. Once positive, they usually stay positive for life, even after successful treatment. So they show that a person has been exposed at some point, not whether the infection is active now.

Non-treponemal tests

These measure a different kind of response that rises and falls with how active the infection is. Names a lab might use include RPR and VDRL. The result comes as a number, called a titer.

This is why the two types are used together. One confirms past or present exposure. The other helps show activity and gives a starting number to compare against after treatment.

Why a second test is often needed

If one test is reactive, the CDC says the other type is used to confirm the result. Non-treponemal tests can occasionally react for reasons other than syphilis, which is called a false positive. A clinician reads the two results together with the person's history and exam.

Timing

Antibodies take time to appear after exposure. The CDC describes this as a window period. Because it varies, a clinician can explain what a test taken soon after an exposure can and cannot show, and whether to repeat it.

Who is advised to test

The USPSTF recommends screening for syphilis in people at increased risk. It also recommends screening for everyone who is pregnant. The CDC also advises people with syphilis to be tested for HIV.

Under Louisiana law (La. R.S. 40:1121.21, as posted by the Louisiana Legislature), prenatal care providers offer HIV and syphilis blood tests at the first prenatal visit and again in the third trimester. Providers also test during labor and delivery. The patient is told testing will happen, and it is not done if she declines.

Is syphilis curable?

Yes. The CDC says syphilis can be cured with the right antibiotic. For all stages, the CDC STI Treatment Guidelines (2021) name penicillin as the preferred treatment. A clinician decides the form, how long it is given and which stage is being treated. Treatment is not something to guess at or begin on one's own.

Treatment stops the infection from getting worse. The CDC notes it does not undo damage that has already occurred, which is another reason earlier testing helps.

Safety profile and cautions

Penicillin allergy. A person who has had a reaction to penicillin should tell the clinician. The CDC says penicillin allergy testing or other plans may be considered, and the clinician chooses the approach.
Pregnancy. The CDC guidelines describe penicillin as the recommended treatment during pregnancy. A pregnant person with an allergy is typically referred for further evaluation by a clinician.
Short-term reaction. The CDC describes a reaction called Jarisch-Herxheimer that can happen within the first day after treatment starts. It can bring fever, chills, headache and aches. It is usually brief, and a clinician can advise on how to manage it.
Other drugs. Other antibiotics are sometimes used when penicillin is not an option, and that is the clinician's call.

Partners

The CDC advises that recent sex partners be tested and, depending on the situation, treated. Louisiana's expedited partner therapy law (La. R.S. 40:1121.6) covers chlamydia and gonorrhea. A 2026 act (Act 567, effective August 1, 2026) broadens it, according to the Louisiana Legislature's bill page, but the final text was not confirmed. Syphilis partners are generally evaluated in person, so ask the clinic how to arrange that.

Follow-up blood tests after treatment

After treatment, the CDC says a clinician repeats the non-treponemal blood test at set intervals over the following months. The goal is to see the titer fall, which suggests the treatment worked. The number of visits and the timing depend on the stage and on the person.

The treponemal test usually stays reactive for life. That is expected and is not a sign that treatment failed.

The CDC also says that sex partners should wait to have sex until treatment is complete and any sores have healed. A clinician can say when that is.

Having had syphilis once does not protect against getting it again. Repeat testing is part of routine care for some people. A clinician can suggest how often.

Where to get tested in Baton Rouge

A local testing list covers more detail on each option. Here is a summary of places that the CDC's GetTested directory lists as offering syphilis testing. Hours and eligibility change, so call before going.

Clinic	Address and phone	Cost and access listed
Metro Health	950 Lorri Burgess Ave, 70802. 225-338-9333	CDC GetTested lists free STI and HIV tests, and lists walk-in access. Hours are not listed.
Open Health Care Clinic (HAART Clinic)	3849 North Blvd, 70806. 225-655-6422	CDC GetTested lists free tests and says to contact the clinic about eligibility.
CareSouth, Baton Rouge Clinic	3140 Florida Blvd, 70806. 225-650-2000	CDC GetTested lists a sliding scale, and insurance, Medicaid and Medicare accepted.
RKM Primary Care	455 E Airport Ave, 70806. 225-683-1320	CDC GetTested lists a sliding scale, and insurance, Medicaid and Medicare accepted.
Baton Rouge Primary Care Collaborative, Plank Road Clinic	7050 Plank Rd, 70811. 225-774-1120	CDC GetTested lists a sliding scale, and Medicaid and Medicare accepted.
CrescentCare, Baton Rouge Office	4550 North Blvd, Ste 230, 70806. 225-302-5968	No cost information is listed. Contact the clinic about eligibility.
East Baton Rouge Parish Health Unit	353 N 12th St. 225-242-4860	CDC GetTested lists sliding-scale fees and appointments required. Services may have changed, so call ahead.

A newer option is the AIDS Healthcare Foundation HIV Specialty Clinic at 8425 Cumberland Place. WAFB reported on August 4, 2025 that it offers HIV and STI screening for patients 14 and older, Monday to Friday, 8 a.m. to 4:30 p.m. The report does not give a phone number or say whether testing is free, so verify with AHF.

The Louisiana Health Hub also runs a hotline at 1-800-992-4379 (Monday to Friday, 8 a.m. to 4 p.m.) and points to the CDC locator at gettested.cdc.gov for current listings.

Quality indicators when choosing where to test

The clinic can name which tests it runs, including syphilis, and explain what results mean.
It offers a follow-up plan if a result is reactive.
It can discuss treatment with a licensed clinician on site or by referral.
It tells you plainly what it charges, or says to ask.

For HIV only, the Louisiana Health Hub notes that home HIV tests are sold at many drugstores. It did not list a state-run mail-in program for other STIs. Access Health Louisiana offers a free HIV home test kit for southeast Louisiana residents aged 18 to 64, but whether Baton Rouge addresses qualify was not stated, so ask them at 504-226-2976. A home HIV test does not check for syphilis.

Privacy, minors and reporting

Under La. R.S. 40:1121.8 (Louisiana Legislature), a minor who has or believes they have a venereal disease may consent to care from a hospital, public clinic or Louisiana-licensed physician. No parent's consent is needed. The statute sets no minimum age.

The same law says a physician or medical staff member may, but is not required to, tell a parent or guardian about the treatment, even over the minor's objection. So a teen who wants privacy can ask the clinic how it handles that.

Under Louisiana's Sanitary Code (La. Admin. Code tit. 51, Part II, section 105), providers report syphilis to the health department by the end of the next business day. Chlamydia and gonorrhea are reported within five business days. Reporting allows public health staff to follow up on treatment and partners.

Louisiana's HIV exposure law was rewritten by Acts 2026, No. 177, effective August 1, 2026. It concerns HIV only and not syphilis. Anyone with questions about it can ask a clinician or the health department.

Questions to bring to a clinician

Which tests will you run, and when will I get results?
If a test is reactive, what happens next?
How will you tell me about follow-up blood tests?
Do I need an HIV test or other STI tests too?
How should my partners be tested or treated?
Is doxy-PEP or PrEP something I should talk about?

For PrEP, Louisiana TelePrEP (Louisiana Health Hub) offers virtual care to eligible adults, and trained pharmacists can dispense PrEP and PEP to people 17 and older under Act 711 of 2024. Clinics such as CareSouth and Metro Health also list PrEP services.

Key takeaways

Syphilis is caused by a bacterium, and it is curable with treatment from a clinician.
Signs such as a painless sore or a rash that does not itch can be easy to miss, and they fade on their own even when the infection remains.
Two types of blood tests are used together, and follow-up tests show how treatment is going.
Louisiana ranked 8th for primary and secondary syphilis in CDC's 2023 report. Local numbers should be requested from the health department.
Free and low-cost testing is available across Baton Rouge. Call ahead to confirm hours and eligibility.

Syphilis in Baton Rouge: Symptoms, Testing and Treatment