What Does a Faint Syphilis Rash Look Like?

Syphilis is a sexually transmitted infection (STI) caused by the bacterium Treponema pallidum. At times, it can be passed on via nonsexual contact.

The initial sign of a syphilis infection, which can take two to three weeks to appear, is a painless bump on the genitals, mouth, rectum, or skin. Swollen lymph nodes around the bump might also be a symptom.

During the secondary phase of syphilis, which occurs four to eight weeks after the first phase, a person might experience a rash. A syphilis rash can be noticeable or faint.

This article will provide an overview of what a syphilis rash looks like, diagnosing and treating a syphilis rash, and additional signs of syphilis.

Identifying a Syphilis Rash

There are several symptoms that can help identify a syphilis rash. A syphilis rash can disappear on its own or disappear and reappear for up to two years. However, regardless if a rash remains or disappears, the bacterium that causes syphilis remains in the body.

Appearance

A syphilis rash usually appears:

• Dark brown or red
• Flat
• Either very visible or faint
• Spotty

In some cases, syphilis can look like rashes from other conditions. A syphilis rash can also appear:

• Pimply
• Blistery
• Clustered

Location

A syphilis rash can be found on:

• The palms of the hands
• The soles of the feet
• Other areas of the body

Feel

A syphilis rash usually feels flat and rough.

 Other Conditions that Look Similar

Since a syphilis rash can be faint and located on other parts of the body aside from the feet and hands, it can mimic other conditions. This can make diagnosis challenging.

The following are some conditions that syphilis can be confused for:

• Genital or oral herpes: A viral STI that can result in sores in the same areas that syphilis can infect
• Viral rash: A rash caused by a viral infection that can appear and disappear
• Medication allergy: A rash that could be a side effect of or reaction to a medication
• Psoriasis: An autoimmune disorder in which the body overproduces skin cells
• Sarcoidosis: A rare disorder of swollen tissues, often around the lymph nodes
• Thrush: A yeast infection that can affect the genitals and other areas

 Are There Tests to Diagnose Syphilis?

Syphilis is usually diagnosed with a blood test. At times, a spinal fluid test is conducted. There might be a second test to confirm a syphilis infection if the blood test is positive.

There are also at-home syphilis tests, which entail taking a sample at home and mailing it to a lab for testing.

How to Treat a Syphilis Rash

Syphilis is treated with antibiotics like penicillin.

Syphilis treatment also includes:

• Blood tests at three, six, 12, and 24 months after treatment to check if the bacterium is still present
• Avoiding sexual contact when sores are present
• Using condoms until follow-up tests are complete
• Treatment for any sexual partners of a person who has syphilis symptoms, a diagnosis of syphilis, or another STI

Additional Signs of Syphilis

The secondary stage of syphilis includes several other possible symptoms, including:

• Wartlike lesions around the genitals, mouth, vagina, penis, or skin folds that can be like blisters that sometimes leak fluid
• Fever
• Loss of appetite
• Muscle and joint pain
• Swollen lymph nodes
• Changing vision
• Hair loss

In cases in which syphilis affects the nervous system (the system of the brain, spinal cord, and its nerves), a person might experience:

• Stiff neck
• Headache
• Hearing loss
• Reflex issues
• Paralysis

Summary

Syphilis is a bacterial infection usually transmitted through sexual contact. The first, or primary, stage of syphilis begins two to three weeks after infection. Symptoms of the primary stage are a painless wartlike lesion at the mouth, genitals, anus, or another part of the body and swelling around the wart.

The secondary phase of syphilis includes syphilis rash, which usually appears as rough, dark red or brown spots on the palms or the soles of the feet. At times, syphilis rash can be faint or appear on other parts of the body.

Diagnosing syphilis usually requires a blood test, and it's usually treated with an antibiotic. Other signs of syphilis include warts, fever, loss of appetite, and muscle pain.

A Word From Verywell

While the first symptoms of syphilis—a painless wart and swelling lymph nodes—can seem harmless and disappear, syphilis remains in the body until it's treated.

Waiting for the secondary stage of syphilis, which is when the syphilis rash appears, to self-diagnose or to get treatment is not an effective way to address this STI. This is because a syphilis rash can be faint or mistaken for other disorders.

Considering that syphilis can be cured by a round of antibiotics, getting tested and seeking treatment can be a simple process. If you don't feel comfortable testing for an STI at a clinic, there are at-home tests available for extra privacy.