Many conditions can cause flaky patches or “rings” on the skin that could be confused with ringworm. They include pityriasis rosea, Lyme disease, nummular eczema, and psoriasis.

Ringworm is an itchy, round rash caused by a fungus called tinea. Usually, ringworm fades away after a person applies antifungal cream for 7–10 days. Other rashes may look like ringworm but will not respond to treatment with an antifungal cream.

The following photos show skin conditions that can cause scaly patches or rings on the skin and may resemble ringworm. Each rash type has a range of treatments and prevention strategies.

Pityriasis rosea on a darker skin toneShare on Pinterest
Pityriasis rosea on a darker skin tone.

Pityriasis rosea is a mild skin rash that may last for 6–8 weeks and often clears up on its own.

The initial signs of infection include headache, fever, and cold-like symptoms. Soon after, a single scaly patch, about 2–10 centimeters (cm) in size, forms on the torso or neck.

The rash is not painful but may be itchy. In those with darker skin tones, it may appear gray, dark brown, or black and can cause flat dark spots lasting several months. In those with lighter skin tones, it may appear pink or red but rarely forms scars.

The cause of pityriasis rosea is most likely the cold sore virus. But rosea sores are not contagious and cannot spread to others through physical contact. Also, pityriasis rosea can occur after a COVID-19 infection.

Contact dermatitis is a form of eczema that results from an irritant substance coming into contact with the skin.

As contact dermatitis can cause patches of thickened, scaly skin, it can be confused with ringworm. The patches may appear dark brown, purple, or gray on darker skin tones, while they usually appear bright red on lighter skin tones.

A person with contact dermatitis may be allergic to certain metals, such as nickel or cobalt, ingredients in cosmetics or soaps, or materials, such as latex.

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Granuloma annulare on a medium-dark skin tone.
Jesus Hernandez

Granuloma annulare is a rare, chronic skin disorder. There are many types of granuloma annulare, but the most common type is localized, primarily affecting children.

In this condition, a raised round rash forms with a distinctive border of small, firm bumps. These bumps grow into a ring and mainly develop on the feet, legs, hands, or arms. The rash can appear deeper in color on darker skin, with a purplish-red edge around the outside. On lighter skin tones, the site may be yellow, red, or flesh-colored.

Experts are not sure exactly what causes granuloma annulare, but it may involve:

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Nummular eczema on a lighter skin tone.
Lester V. Bergman/Getty Images

Nummular eczema, also known as discoid eczema, is a disorder that causes coin-shaped patches of itchy, swollen skin to appear. This type of eczema occurs mainly on hands, arms, or legs and sometimes on the trunk.

Ringworm and nummular eczema both look similar because of a circular rash pattern. However, nummular eczema starts as tiny spots that turn into a rash. In contrast, ringworm spreads out with a clear center encircled by a discolored ring.

It is not clear what causes nummular eczema. Dry skin, extreme stress, sensitivity to a particular metal, and medication may all be triggers. Also, the symptoms worsen in cold, dry climates and in people with poor blood circulation.

Psoriasis is a common chronic skin condition that develops when the body produces skin cells too quickly. As a result, the cells pile up, forming visible patches on the skin’s surface.

Psoriasis can form anywhere on the body, but it typically appears on the elbows, knees, scalp, and lower back. Patches will appear rose-colored on darker skin and dark red or purple on lighter skin.

Experts believe psoriasis comes from issues with the immune system, causing the body to attack healthy skin cells. It is not contagious, but it can run in families — though it is not always hereditary. The following factors can trigger psoriasis:

  • hormonal changes
  • excessive alcohol intake
  • stress or anxiety
  • injuries to the skin, including insect bites and sunburn
  • infections such as strep throat
  • certain medications, such as anti-inflammatory drugs or high blood pressure medications

Lyme disease is a bacterial infection caused by the bite of a black-legged deer tick.

People with Lyme disease develop a circular bull’s-eye rash around the bite mark. This “target” rash can sometimes be confused with ringworm.

Up to 70% of people in the initial stage of Lyme disease will have a rash appear within 5–7 days after the bite. The area may burn, itch, or feel hot to the touch.

On lighter skin tones, the spot will be bright red. However, on darker skin tones, a pinkish-brown ring may appear around a maroon-red area. Also, the bull’s-eye rash may be harder to see on those with darker skin.

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Lupus rash on a lighter skin tone.
Doktorinternet, CC BY-SA 4.0, via Wikimedia Commons

Lupus is a chronic inflammatory disease that can cause a scaly rash to form on the upper body and face. During a first-time flare, this rash can resemble ringworm.

Since skin symptoms of lupus form on skin exposed to sunlight, a person with lighter skin may develop a pink spot with a dark-brown border on their face, neck, arms, or hands. On a person with darker skin, it may be dark black or light pink with a maroon edge. Lupus flares may form scars as they heal.

The following factors may trigger flare-ups:

  • exposure to sunlight
  • stress, excess work, or lack of sleep
  • infection
  • injury

The symptoms may flare up for a few weeks or longer before improving. Since lupus is a chronic condition, flares can happen again in the same spots or in new areas.

The proper treatment approach for a red, circular rash depends on the cause, and an accurate diagnosis is key.

Depending on the severity of the rash and any other symptoms, a person may benefit from a combination of the following treatments and home care strategies:

  • Avoiding triggers: Conditions such as contact dermatitis, nummular eczema, psoriasis, and lupus can occur or flare up in response to triggers. Identifying and avoiding specific triggers can reduce symptoms.
  • Emollients: Emollients are moisturizing treatments that help soothe and hydrate the skin, reduce itchiness, and prevent inflammation.
  • Topical treatments: Doctors may prescribe topical steroids or antibiotics to treat some underlying causes
  • Prescription medications: Depending on the cause of the rash, a healthcare professional may also recommend steroid injections or tablets, oral antibiotics, biologics, or anti-allergy medications.
  • Light therapy: Some forms of light therapy, such as ultraviolet light therapy, may help with pityriasis rosea, granuloma annulare, nummular eczema, and psoriasis.
  • Cryotherapy: Cryotherapy, which involves freezing areas of skin with liquid nitrogen, can help control granuloma annulare.

If an unexplained rash lasts longer than a few weeks, contact a doctor, such as a dermatologist.

It is essential to receive professional care if the rash:

  • appears over the whole body
  • is painful
  • seems infected
  • produces blisters, especially near the eyes, inside the mouth, or near the genitals
  • occurs with any fatigue or joint pain

The American Academy of Dermatology recommends seeking emergency care if a rash:

  • accompanies a fever
  • accompanies difficulty breathing
  • appears suddenly and spreads quickly

Here are some frequently asked questions about ringworm and other conditions that can cause a rash.

What autoimmune rash looks like ringworm?

Psoriasis and lupus are autoimmune conditions that can cause a rash that looks like ringworm. A doctor may order tests to determine the underlying cause of the rash.

What type of lupus looks like ringworm?

Subacute cutaneous lupus is a type of lupus that can cause a ring-like rash that may resemble ringworm. The condition may also cause a rash that resembles eczema or psoriasis.

Rashes that are circular and scaly do not always indicate ringworm. Instead, they can result from several common health issues, some more serious than others.

Different treatments are available, and the best approach depends on the rash’s cause and severity.

Anyone with an unexplained rash should receive a professional diagnosis. If a rash appears and spreads quickly, or if it occurs with a fever or difficulty breathing, contact emergency services.