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What is syphilis?

Syphilis is an STI, or sexually transmitted infection. It's caused by the bacterium Treponema pallidum. You may know STIs by the name STD, or sexually transmitted disease.

Syphilis is most commonly passed on through sexual contact. It affects both men and women. It's easy to pass on to sexual partners and can cause permanent damage if left untreated.


Syphilis is a bacterial infection most often spread through unprotected sex (sex without a condom or other barrier in place). An infected person who doesn't seek out treatment can spread the infection even without showing symptoms. Untreated syphilis can cause long-term health problems throughout the whole body. This includes problems with the kidneys, brain, eyes, liver and nervous system.

Risk Factors

Anyone who has sex runs the risk of contracting syphilis. But you may be more likely to contract syphilis if you:

  • Have unprotected or unsafe sex
  • Have sex with multiple partners, especially partners who are not tested for STIs regularly
  • Are a man who has sex with men
  • Are infected with HIV
  • Have a partner who has been diagnosed with syphilis
  • Use illicit drugs

Symptoms and How It Works

Syphilis is different from other STIs, like chlamydia or gonorrhea. It's unique because it occurs in stages.

There are four main stages of syphilis.

Primary syphilis: The first sign of syphilis is a painless sore (chancre) on the genitals, rectum, anus, or mouth that occurs on average 2-3 weeks after infection occurs. It is usually a small, red bump that progresses to an ulceration. It's easy to miss this stage, because the chancre may appear within the vagina or anus, and is painless-so goes unnoticed. Some people also experience swollen lymph nodes in this stage.

Secondary syphilis: A few weeks after the chancre heals, you may develop a red or brown rash. It usually begins on the trunk or torso, then spreads to the rest of the body, including hands and feet. The rash usually isn't itchy. It may come and go repeatedly during the secondary stage of syphilis, that can last months. In light-skinned people, these sores appear dark. In dark-skinned people, they may appear lighter than the skin. fever, swollen lymph glands, sore throat, patchy hair loss, headaches, weight loss, muscle aches, and fatigue” are also experienced, according to CDC. Fever, swollen lymph nodes, fatigue, muscle aches, joint aches, and headaches are additional common symptoms during secondary syphilis. Some persons also experience hair loss, weight loss, dizziness, visual problems, confusion, or wart like lesions in the mouth or genital area.

Latent syphilis: Latent syphilis generally occurs weeks to months after secondary syphilis. It is a time when untreated infection remains in your body, but you no longer feel the symptoms like rash, fever, fatigue, and joint aches that occured in secondary syphilis. You may not feel ill at all, but you can still spread the infection to others. A healthcare provider can order a blood draw, to see that you have been infected previously (this blood draw can also be ordered during primary and secondary syphilis, though occasionally in primary syphilis the infection is too early to see in your blood. Occasionally, you can relapse from latent syphilis, to experience symptoms of secondary syphilis again.

Tertiary/late syphilis: This is the most serious stage of syphilis and causes the most lasting damage. It may not present until many years after the untreated syphilis infection occurred. It is estimated that up to 4 out of 10 people who are infected with syphilis will develop tertiary syphilis. In this stage, syphilis may damage the "brain, nerves, eyes, heart, blood vessels, liver, bones, and joints." (Mayo Clinic) It may develop into neurosyphilis, which can cause severe headache, problems coordinating movement, paralysis, numbness, confusion, memory problems, dementia, and even death.

Common Syphilis Treatment

The good news is-syphilis is curable. Antibiotics are the best treatment for bacterial infection, including syphilis. Penicillin is the most commonly prescribed antibiotic for treating syphilis. But if you’re allergic to - or have negative side effects from - penicillin, there are other options. Other antibiotics used to treat syphilis include doxycycline and tetracycline.

Chlamydia treatment

Fortunately, Chlamydia is easily treated with antibiotics. Azithromycin and doxycycline are antibiotics that are effective at treating chlamydia. Duration of antibiotics may be one day, or for one week, depending on which antibiotic you are prescribed.It’s important to not have sex until you and your current sexual partner/s have also finished treatment. You should avoid having sex for seven days afterwards. This is important for the infection to be fully cured in both people before resuming sexual activity. If it is not, you risk becoming reinfected.. Ask your healthcare professional when it’s safe to have sex again.Remember that if you’ve been treated for chlamydia, you can still get infected again. For this reason, it is recommended that persons who test positive for chlamydia, have repeat testing in 3 months, to ensure they have not contracted the infection again.

What is the treatment for syphilis if you can't have antibiotics?

There is no common medicine for syphilis other than antibiotics. If you cannot have antibiotics, your doctor may recommend a penicillin desensitization treatment. This is a specialized process that allows you to take penicillin-even if you have been allergic to it in the past.

When to speak to a doctor

Syphilis diagnosis and treatment is important for keeping you healthy, because untreated syphilis can have severe long-term health problems. If you repeatedly have risk factors and /or unprotected sex, you should consider testing for syphilis at regular time intervals-especially because symptoms of initial infection can be easily missed. Online syphilis treatment will likely include drawing your blood to check for the infection, and getting you antibiotic treatment if you are infected. Your online provider can send orders for lab work to a lab located near you, and coordinate treatment in a location near you, as well. If you do not have a known allergy to penicillin, then the recommended treatment for primary, secondary, and latent syphilis is an injection of penicillin antibiotic into your muscle, usually done in the thigh or buttox area. Patients with tertiary syphilis are treated with intravenous antibiotic infusions. Often these patients are quite ill, and treated in the hospital.

You can get a full STI check online when you schedule an appointment with one of our Babylon primary care doctors. Simply download the app and create an account today.


Prevent and manage syphilis with these precautions:

  • Always use a condom or a dental dam when you have sex. Transmission can occur during vaginal, oral, and anal intercourse.
  • Visit a healthcare provider for regular STI screenings. Provider visits are safe, confidential, and non judgemental. Providers welcome the opportunity to discuss your concerns because they want to keep you healthy!
  • Ask your partner(s) to be tested for STIs
  • Avoid sexual contact until treatment has been completed to prevent spreading
  • Avoid sharing sex toys


The information provided is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Seek the advice of a doctor with any questions you may have regarding a medical condition. Never delay seeking or disregard professional medical advice because of something you have read here.