How to Identify 4 Common Skin Rashes

A rash is an area of irritated or swollen skin. It may be red and itchy or painful. And it can involve blisters, bumps, raw skin.

Rashes can be a response to an allergy, toxin, infection, or systemic disease. They range from minor tissue swelling to an outbreak of painful sores.

Some rashes affect a small area while others are widespread. They're sometimes tough to tell apart—even for a trained eye.

Broadly speaking, a rash can be classified as either infectious or non-infectious. Many types and possible causes exist.

This article will help you learn to identify:

  • Impetigo
  • Athlete's foot
  • Psoriasis
  • Shingles

Impetigo

Impetigo rash beneath a mans lower lip

SCIENCE PHOTO LIBRARY / Getty Images

Impetigo is a common skin infection. It's usually caused by either Streptococcus (strep) or Staphylococcus (staph) bacteria.

Impetigo is most common on the face or limbs. Its distinctive features are:

  • An eruption of red sores
  • Clear fluid or pus leak from sores
  • Formation of a honey-colored crust

Bacteria typically enter your body through a cut, scrape, burn, or insect bite.

Children often get impetigo after a cold. Using tissues makes the skin around their noses raw. And that gives the bacteria easy access. 

The honey-colored crust is usually a tell-tale sign of impetigo. Still, your healthcare provider may order a bacterial culture to confirm the diagnosis.

When impetigo involves large blisters (known as bullae), it's called bullous impetigo. It's a less common form. Young children are most likely to have it.

Impetigo may cause minor itchiness. But it's generally not painful. That sets it apart from shingles and other types of eruptive lesions.

Impetigo is typically treated with antibiotics.

Recap

Impetigo is a bacterial infection. It causes leaking red sores on the face or limbs. The fluid forms a distinctive honey-colored crust. It isn't painful. Impetigo is treated with antibiotics.

Athlete's Foot (Tinea Pedis)

Athlete's foot

 ussaquarius / Getty Images

Athlete's foot (tinea pedis) is a common fungal infection. Symptoms include:

  • A red rash between the toes or on the soles of the feet
  • Flaking or broken skin
  • Discomfort ranging from mild itchiness to painful blisters

Athlete's foot between the toes is called interdigital tinea pedis. When it's mainly on the soles, it's moccasin-type tinea pedis. Blister-like outbreaks are acute vesicular tinea pedis. (Vesicle means blister.)

Athlete's foot spreads easily in moist, unhygienic environments. That can include spas and locker room floors. It's treated with topical antifungals.

Healthcare providers often diagnose athlete's foot on appearance alone. But other conditions like plaque psoriasis can cause similar symptoms. So you may be tested for those if your rash doesn't respond to antifungals.

Recap

Athlete's food is a fungal infection. It's most common between the toes or on the soles of the feet. Painful blisters may form. Althete's food is treated with antifungal medicines.

Psoriasis

Psoriasis (plaque type)

DR P. MARAZZI/SCIENCE PHOTO LIBRARY / Getty Images

Psoriasis is an autoimmune skin disorder. It's chronic and inflammatory. Triggers may include:

  • Stress
  • Medications
  • Infection
  • Skin injury
  • Environmental triggers like the sun

Between 1% and 8% of the global population has psoriasis.

In autoimmune disorders, your immune system mistakenly attacks healthy tissues. This triggers inflammation.

In psoriasis, the skin cells are attacked. New ones are produced faster than the old ones can be shed. That leads to a buildup of cells—the psoriasis rash.

Plaque psoriasis is the most common form of psoriasis. Symptoms include:

  • Red or dark patches of skin covered with thick, silvery scales
  • Itching, burning, and/or soreness
  • Flaking, cracked, dry skin that can bleed when scratched

Plaque psoriasis is most common on the elbows, knees, and scalp.

Other types of psoriasis are:

Psoriasis is often diagnosed by its appearance. It may require a skin biopsy for confirmation.

No blood tests can diagnose psoriasis. Your healthcare provider may rule out similar skin conditions such as:

Treatment varies by the severity of the outbreak. It may include topical steroids, immunosuppressants, and UV light therapy.

Psoriasis sometimes goes away without treatment. It can recur suddenly, as well.

Recap

Psoriasis is an autoimmune disorder. The immune system kills skin cells and they stack up. The most common form is plaque psoriasis. Treatment depends on its severity.

Shingles

Herpes Zoster (Shingles)
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Shingles (herpes zoster) is a painful rash. It's caused by a reactivation of the varicella virus. That's the virus that causes chickenpox.

The lifetime risk of developing shingles can run anywhere from 20% to 30%. High-risk groups include people with compromised immune systems. 

Shingles typically strikes later in life. Symptoms often come in two phases:

  • Pre-eruptive stage: A dull, localized ache and increased sensitivity to touch.
  • Eruptive stage: Tiny, painful blisters appear. They may burst and scab over.

Shingles is contagious during the blistering phase.

Shingles almost always affects just one side of the body. It's a nerve infection and is limited to an area of skin supplied by a single nerve. This area is called a dermatome.

The pain of shingles ranges from prickly, persistent discomfort to deep, excruciating pain.

Shingles sometimes causes long-term nerve pain. This is called postherpetic neuralgia. Older adults and those whose shingles is untreated are at higher risk.

See a healthcare provider as soon as you recognize the rash with fluid-filled blisters. Early treatment with antiviral drugs such as Zovirax (acyclovir) can shorten the outbreak. It also keeps it from spreading to vulnerable parts, like your eyes.

A highly effective shingles vaccine known as Shingrix (recombinant zoster vaccine) is available. Vaccination is recommended for all adults 50 and older.

Recap

Shingles is caused by the chickenpox virus becoming active again. After a dull, aching phase, tiny, painful blisters erupt. Shingles is treated with antiviral drugs. A vaccine is available.

Summary

Rashes are irritated skin. They can be caused by many different things. They each have distinguishing features.

  • Impetigo: Bacterial infection. Involves red sores that leak fluid. Fluid forms a honey-colored crust that's easy to recognize.
  • Athlete's foot: Fungal infection. Strikes between the toes and on the soles. Causes a red rash and broken skin that can be itchy or painful.
  • Psoriasis: Autoimmune disease. The immune system attacks skin cells. Cells build up and form plaques with silvery scales.
  • Shingles: Reactivated varicella virus. Involves tiny, painful blisters on one side of the body and sensitivity to touch.

A Word From Verywell

If you develop a rash and don't know what it's from, get medical attention.

The rash itself may not be harmful. But it could be a symptom of a condition that needs to be treated.

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9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  3. National Center for Biotechnology Information, U.S. National Library of Medicine: StatPearls. Impetigo.

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  5. National Center for Biotechnology Information, U.S. National Library of Medicine: StatPearls. Tinea pedis.

  6. National Center for Biotechnology Information, U.S. National Library of Medicine: StatPearls. Psoriasis.

  7. National Center for Biotechnology Information, U.S. National Library of Medicine: StatPearls. Plaque psoriasis.

  8. National Center for Biotechnology Information, U.S. National Library of Medicine: StatPearls. Herpes zoster.

  9. Centers for Disease Control and Prevention. What everyone should know about shingles vaccines.