Syphilis is a sexually transmitted bacterial infection that may cause sores on the genitals, anus, and in or around the mouth.
Syphilis can be spread through any type of contact with these sores.
Oral syphilis can appear on the tongue, gums, or anywhere else inside the mouth.
Chancres can also show up on the lips or around the mouth.
In this article, I’ll talk about the causes of syphilis, what other symptoms can occur with syphilis, how syphilis tongue sores are treated, precautions to take, and how to prevent syphilis.
Syphilis on Tongue Causes
Syphilis is a sexually transmitted infection (STI) that is caused by a bacteria known as Treponema pallidum.
It has been around for centuries, and is still a common STI today.
The sores caused by syphilis are known as chancres.
Syphilis is spread via contact with chancres, which can occur during any type of sexual contact or kissing.
It may also be passed to an infant before or during birth.
Syphilis does not always cause symptoms, so it is not always possible to know if you came into contact with it.
If you are sexually active and develop sores on your tongue or in or around your mouth, see your medical provider for an examination.
Risks of oral syphilis
Syphilis is easily treated with antibiotics like penicillin or doxycycline.
Risks of untreated syphilis can include long-term health problems, specifically affecting:
- The heart
- The brain and nervous system
- Muscular function
It can take years or even decades before serious effects of syphilis become known.
Not treating syphilis can also put future pregnancies at risk, leading to increases in miscarriage or stillbirth risk, as well as passing on the infection during pregnancy or birth.
Syphilis can also increase risks associated with HIV infections.
Symptoms of Oral Syphilis
Syphilis infections happen in stages.
While there are common symptoms for each stage, not everyone will get all symptoms.
Sometimes a person can have no symptoms and still be contagious.
Oral symptoms of syphilis typically occur in stages one and two.
Small sores known as chancres may appear on the tongue or in or around the mouth.
Someone may only have one sore, or they may have several. It is most common to only have one sore.
Symptoms of oral syphilis typically appear around 21 days after exposure, although may show up anywhere between 10-90 days.
Syphilis oral lesions are painless.
They heal on their own in 3-6 weeks, but a sore healing and disappearing does not mean the infection is cleared.
Only antibiotic treatment can cure syphilis.
Secondary stage syphilis also includes mouth sores that are more like warts.
These will also resolve on their own in 4-6 weeks, but a person can still be contagious and have an active infection even after they resolve.
Stages of Syphilis
Syphilis infections happen in four stages.
Patients may not always experience every symptom.
Until syphilis is treated, a person is still infected and may be contagious, even when symptoms go away.
Syphilis typically first presents with a sore known as a chancre.
One or more sores may appear anywhere in or around the mouth, the genitals, or the rectum.
They may appear 10-90 days after exposure, but most commonly show up around 3 weeks after exposure.
Chancres may look like an ingrown hair or a small cut.
They are round, hard, and typically not painful.
Primary syphilis symptoms typically resolve on their own in 3-6 weeks.
But even when symptoms are gone, a person is still contagious and actively infected with syphilis.
Early diagnosis decreases the risk of serious health problems.
The secondary stage of syphilis can happen right after the primary stage.
It may also happen weeks or months later.
Symptoms typically include a red or pale rash that may appear in one spot, or all over the body.
Red or brown spots may also form on the hands and feet.
Lesions that are white or gray may appear around the groin, armpits, mouth, and/or nose.
This phase of syphilis may also include hair loss, sore throat, fever, headaches, swollen glands, and fatigue.
Symptoms often go away on their own within 4-6 weeks, but without antibiotic treatment, a person still has an active syphilis infection and may still be able to transmit it to others.
People may still be contagious with syphilis in the early latent stage, but as symptoms resolve and have been gone for a longer time, people who are infected may no longer be contagious.
While the latent phase does not involve any symptoms, a person still has syphilis and is at risk for developing long-term health complications.
Around 15% of people who have syphilis will progress out of the latent phase into the tertiary phase.
It can happen 10-30 years after the initial infection.
During this phase, serious and permanent damage may occur to organs such as the heart, eyes, ears, and brain.
Muscle and nervous system function may be affected.
An increased risk of developing dementia is also possible.
Syphilis can still be treated in the tertiary stage, but treatment cannot undo permanent organ damage.
Treatment for Oral Syphilis
Oral syphilis symptoms are treated the same way as syphilis symptoms that appear anywhere else.
Syphilis is a systemic infection that affects the whole body, regardless of where chancres or other signs appear.
Syphilis spreads through the body via the blood and lymphatic systems, even if primary infection occurs in the mouth.
If you develop a sore on the tongue or in or around the mouth, a healthcare provider or dentist will likely perform a physical exam.
To confirm a diagnosis, they may order blood work or take a small amount of fluid or tissue from the sore.
This allows for close examination of the bacteria that causes the infection. Most syphilis is treated with penicillin.
It may be treated with doxycycline or other antibiotics if someone is allergic to penicillin.
The dosage of antibiotics depends on how long someone has had syphilis.
Later stages require longer courses and higher doses of antibiotics.
If you are being treated for syphilis, it is important to follow through on the complete treatment protocol, and to make sure you do not engage in any sexual contact during treatment, as it can still be contagious during treatment.
If your partners have not been treated, it is still possible to get reinfected if you have sexual contact.
Signs and symptoms of syphilis may resolve on their own without treatment, but will not be cured.
Only a full course of antibiotic therapy can cure a person from syphilis.
If not treated, syphilis can spread to the brain, eyes, and ears, and cause severe damage.
Precaution and Prevention
You can decrease your risk of being exposed to syphilis by practicing safe sexual hygiene and using proper protection at all times.
If you have multiple sexual partners, getting tested for syphilis is a good precaution, since people can pass syphilis on without any active signs of infection.
Some people may never know they have syphilis.
Ask new sexual partners to get tested before having sexual contact with them.
Avoid sexual contact of any kind with someone who has syphilis until they have completed their full course of treatment.
Use condoms and other barriers properly during vaginal, anal, or oral sex.
It is still possible to contract syphilis if chancres are present, even with proper condom use.
If you have been diagnosed with syphilis, let current and past sexual partners know.
Your doctor may be able to tell you how long ago you contracted it.
When to See a Medical Provider
See a medical provider if you develop any type of sore on or around your genitals or mouth, particularly if you are sexually active.
The sooner that syphilis or other sexually transmitted infections are treated, the easier it is to avoid complications and spreading the infection.
Signs of sexually transmitted infections to be aware of include:
- Sores or lesions in or around the mouth
- Sores, warts, bumps, or lumps around the genitals, anus, or groin
- Rash that lasts for more than 1-2 days
- Rash on the hands or feet
If you are worried about syphilis or other STDs, speak to a medical provider. In minutes, you can chat with a K Health primary care provider to ask questions and get answers from a qualified medical professional.
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Frequently Asked Questions
K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.
K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.
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Syphilis: CDC Fact Sheet. (2022).
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Oral findings in secondary syphilis. (2018).
Primary Syphilis of the Oral Cavity, a Rare Presentation of a Re-Emerging Disease. (2021).