What is syphilis?

Syphilis is an infection caused by the bacteria Treponema pallidum. It can lead to life-threatening conditions if it is not treated. Syphilis is a sexually transmitted infection (STI), which means that it is spread by having sex with an infected person. If you have syphilis, you can spread it to others. Both men and women can get the disease. Without treatment, the infection can lead to:

  • Heart disease
  • Nerve disorders
  • Brain damage
  • Mental disorders
  • Blindness
  • Aortic aneurysms

These complications develop over many years.

What are the symptoms of syphilis?

The symptoms of syphilis depend on the stage of the infection. The stages of syphilis are:

Primary syphilis

  • A smooth, red, painless sore—or chancre—develops on a sex organ or in the mouth. (The sore also can develop on the inside the body, where it cannot be seen.) The sore goes away on its own in one to six weeks.

Secondary syphilis

  • After the chancre goes away, a pinkish, bumpy skin rash may appear on all or parts of the body.
  • Fever, sore throat, body aches, headache, loss of appetite or other flu-like symptoms may appear. These symptoms can be mild and can come and go over one to two years.
  • This stage is the most contagious of all stages. Approximately one-third of untreated individuals with primary syphilis will progress to this second stage. In secondary syphilis, the bacteria have spread in the bloodstream and have reached their highest numbers. Without treatment, up to one-third of patients will develop complications of late-stage syphilis.

Latent syphilis

  • With latent syphilis, the infection is not contagious but may affect the heart, brain, nerves, eyes, bones and other parts of the body.

Don’t be fooled by the mild warning signs. If you are worried about syphilis, get checked. Syphilis is a serious disease.

Is it true that a person with syphilis can't spread the infection?

No. A person with syphilis can spread the infection during the first two stages of the disease. If you come in contact with an open sore (first stage) or skin rash (second stage), you can pick up the bacteria that cause the infection. If the bacteria enter your body through an opening such as the penis, anus, vagina, mouth or broken skin, you can get syphilis.

If a person has had syphilis for more than two years (latent syphilis), it’s unlikely that he or she can spread the disease. Don’t take a chance. Use a condom and spermicide during sex.

How can I know if I have syphilis?

If you think you have syphilis, or any STI, contact your health care provider. He or she can examine you and perform tests to determine if you have an STI.

To check for syphilis, your health care provider:

  • Examines your sex organs for chancres and skin for rashes.
  • Takes a small sample of blood. Signs of the infection may not show up in your blood for up to six weeks after you have been infected.

You may need to wait for several days to get your test results. If you have had another STD, you should also get checked for syphilis.

Can syphilis be cured?

Yes, the infection that causes syphilis can be cured. However, damage to organs in the body caused during late-stage syphilis often cannot be repaired.

How is syphilis treated?

Syphilis is treated with penicillin, usually given as a shot. This antibiotic kills the bacteria causing the infection. Since you and your sex partner are both infected, both of you must be treated.

It is important that you continue to take your medication, even if the sore or skin rash goes away. You may need to return to your health care provider to be rechecked for the infection. Treatment may need to continue for several weeks.

You also should:

  • Tell anyone you have had sex with in the last two years that you are infected. This step is especially important because the symptoms of syphilis are mild and may go unnoticed.
  • Don't have sex unless your health care provider says it’s okay.
  • Get rechecked to make sure the infection has been cured.
  • Get checked for HIV (AIDS) and other STIs (herpes, gonorrhea, chlamydia).

Can I give syphilis to my unborn child?

Yes. If you have syphilis while you are pregnant, it’s possible that your baby will be born with the infection. Syphilis during pregnancy can result in death of the baby. If you are pregnant, you should be tested for syphilis.

How can I protect myself from syphilis?

  • Do not have sex with someone who has an open sore on his or her sex organs or whom you know to be infected.
  • Always use a condom during sex. Also use a spermicide that contains nonoxynol-9.
  • Limit your number of sex partners.

Where can I learn more?

CDC Hotline: 800.232.4636
Centers for Disease Control and Prevention


  • Centers for Disease Control and Prevention. Syphilis Accessed 5/8/2015.
  • Augenbraun M. Chapter 19. Syphilis. In: Klausner JD, Hook EW, III. eds. CURRENT Diagnosis & Treatment of Sexually Transmitted Diseases. New York, NY: McGraw-Hill; 2007. library.ccf.org Accessed 5/8/2015.
  • National Institute of Allergy and Infectious Disease. Syphilis Accessed 5/8/2015.

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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 4/14/2015...#4622