The Call-On-Doc Guide to Syphilis

Syphilis progresses in stages, and symptoms vary depending on how long the infection has been present.

Primary syphilis usually begins with a single painless sore, called a chancre, at the site of infection. This sore may appear on the genitals, anus, mouth, or throat. Although the sore heals on its own within a few weeks, the infection does not go away without treatment.

Secondary syphilis develops weeks to months later and may cause a widespread rash, often involving the palms of the hands or soles of the feet. Other symptoms may include fever, fatigue, sore throat, swollen lymph nodes, or patchy hair loss. These symptoms can also resolve without treatment, leading to false reassurance.

Latent syphilis has no visible symptoms, but the bacteria remain in the body. This stage can last for years.

Tertiary syphilis occurs when the infection is left untreated long-term and can cause severe organ damage, including neurologic, cardiovascular, and vision complications. This stage can be life-threatening.

Symptoms depend on the stage and may be mild or overlooked. Common signs include painless sores, non-itchy rashes, flu-like symptoms, or neurologic changes in advanced disease.

Because symptoms may fade even while infection persists, testing is the only reliable way to confirm syphilis.

Syphilis spreads through direct contact with a syphilis sore during vaginal, anal, or oral sex. It can also be passed from a pregnant person to their baby, resulting in congenital syphilis.

Transmission does not require ejaculation, and sores may be hidden or internal, making exposure easy to miss.

Syphilis is diagnosed with blood tests, which typically include an initial screening test followed by a confirmatory test.

Testing is especially important for:

• People with STI symptoms or known exposure

• Sexually active individuals with risk factors

• Pregnant patients

Early diagnosis allows for effective treatment before complications develop.

Syphilis is curable, particularly when treated early.

The standard treatment is penicillin G, given as an injection. The number of doses depends on the stage of infection. Sexual partners must also be evaluated and treated, and follow-up blood testing is required to ensure the infection has been fully cleared.

What Happens If Syphilis Is Untreated?

Without treatment, syphilis can progress and cause permanent damage, including neurologic impairment, vision loss, heart disease, and pregnancy complications. Early detection prevents these outcomes and protects long-term health.

CallOnDoc provides confidential, judgment-free STI care online.

Through a virtual visit, you can discuss symptoms or exposure with a licensed provider, receive guidance on testing and treatment, and avoid long in-person clinic waits.

Healthcare that fits your life — not your calendar.