How can I Tell the Difference Between Some Common Skin Rashes?

Mary McMahon
Mary McMahon

Many common skin rashes have similar characteristics, so it can be hard to tell them apart without a picture, but there are ways to narrow things down. The first thing you should consider is the location of the rash, since many tend to show up in specific areas. Other things you should consider are how the area feels — for instance, if it is itchy, scaly, or numb — and what the rash looks like. It's also important to note the color of the rash or the color of any discharge, since this can differ between rashes.

Chickenpox is contagious, marked by itchy, red spots, and more common during childhood.
Chickenpox is contagious, marked by itchy, red spots, and more common during childhood.

If possible, you should try to determine what caused the rash too. For instance, it might only happen after you eat certain foods or take certain medications, or it might happen after you go swimming. The more specific information you have about a rash, the easier it usually is to identify it. Though considering these characteristics can be helpful in identifying skin problems, you should consult with a doctor about any rash that comes on quickly, lasts for more than a few days, or is very itchy or painful.

A rash.
A rash.

Location

Where the rash shows up on your body is often one of your best clues as to what it is. Many rashes usually only happen in specific parts of the body, like rosacea or athlete's foot. Others happen in specific patterns, like pityriasis rosea, which is sometimes called the "Christmas tree rash," since it tends to happen on people's backs in a Christmas tree shape. Sometimes the location can also give you a clue to what caused it. For instance, bacterial or fungal rashes tend to show up on places on the body that are wet and warm, like the groin or armpit.

Shingles causes a blistery rash.
Shingles causes a blistery rash.

Seeing that a rash has spread all over the body can be helpful too, since some are characterized by how fast they spread or the patterns in which they spread. For instance, eczema tends to happen on the insides of the elbows or the backs of the knees. You should also note what parts of your body aren't affected by the rash, since that could mean that something stopped it from spreading there. People often see this with contact dermatitis, that often only happens on exposed skin, or with swimmer's itch, which only happens on the parts of the skin that are directly in the water, not those that are covered by a swimsuit or bathing cap.

Eczema is a common skin rash.
Eczema is a common skin rash.

How the Rash Feels

Many common skin rashes are itchy, including ringworm, chicken pox, eczema, and impetigo. This can be because of an allergen, like the oil from a poison ivy plant, or because of a virus, as in the case of chicken pox. It's important not to scratch, since this can often spread the rash around the body or to other people. When trying to tell the difference between itchy rashes, you should consider the location as well as any other feelings that you get from the area, like a burning sensation or dry skin. Rashes like eczema and psoriasis tend to be itchy with dry skin, while hives or miliaria can be itchy and painful. A lack of feeling can also be an identifying sign — for instance, shingles is often burning or painful, but it can cause numbness, and a molluscum contagiosum rash is painless.

Hives can be very itchy.
Hives can be very itchy.

Appearance

The texture of a rash can often be very helpful in identifying it. Skin rashes can be flat, rounded, have raised edges, have blisters or welts, or have thick, hard plaques. Flat skin rashes often come with some inflammation, but not blisters or welts; intertrigo is a good example of this. Many types have blisters, including dermatitis, shingles, eczema, and chicken pox. Sometimes a rash might have bumps instead of blisters, which are raised but not filled with fluid. If the rash is caused by a fungus and has a specific shape it often has raised edges, like ringworm.

Itching, burning feet is often cause by athlete's foot.
Itching, burning feet is often cause by athlete's foot.

The color of the area is important as well. Skin rashes are typically red, pink, or purple, but some also have white scales or plugs. If a rash mostly consists of redness and inflammation, it could be cellulitis, intertrigo, or athlete's foot, depending on the location. If it is only purple, it might be lichen planus. You should also note the color of any liquid or discharge; many have blisters filled with clear fluid, but impetigo blisters are filled with yellow fluid, molluscum contagiosum bumps can be filled with a white, cheesy substance, and rosacea can have pimples filled with pus.

A topical cream can be applied to alleviate itchy skin.
A topical cream can be applied to alleviate itchy skin.

Table of Common Skin Rashes

Lichenoid dermatitis may form on ankles.
Lichenoid dermatitis may form on ankles.
Area Affected: Feels Like: Looks Like: Happens in Response to
Dermatitis The area touched by the allergen. Itchy, burning. Redness, swelling, blisters. Allergens.
Ringworm Body, feet, groin, scalp. Itchy. Raised red scaly rings. Fungus.
Chicken Pox Whole body. Itchy. Blisters filled with clear fluid. Virus.
Shingles Trunk or buttocks, but can be everywhere. Burning, tingly, painful, numb. Raised red dots and blisters. Virus.
Hives Whole body. Itchy, stinging. Raised red welts. Allergens, extreme temperatures, infection.
Impetigo Usually face, arms, legs. Itchy. Blisters with yellow fluid. Staph bacteria.
Swimmer's Itch Skin exposed to water. Itchy, burning. Red bumps or blisters. Parasite.
Rosacea Face. Itching, burning. Redness, inflammation, thick skin, pus-filled pimples. Unknown.
Eczema Knees, elbows, neck, etc. Itchy, dry. Oozing, bleeding blisters and thick patches. Allergens, climate, illness.
Psoriasis Scalp, elbows, knees, lower back. Itchy, dry. Thick red plaques with white scales. Possibly hereditary.
Miliaria Whole body. Itchy, stinging. Clear, fluid filled bumps. Heat.
Drug Rash Whole body. Itchy. Red spots that spread. Medication.
Intertrigo Warm, moist areas. Painful. Red inflammation. Can be bacteria, fungus, or virus.
Lichen Planus Wrist or ankles, lower back, neck, legs. Itchy. Purple or red bumps with flat tops. Possibly allergens.
Cellulitis Legs, usually. Painful. Red inflammation. Bacteria.
Molluscum contagiosum In children: face, trunk, armpits, extremities; in adults: groin. Painless. Flesh-colored bumps with a depression or white plug in the center. Virus.
Pityriasis rosea Chest, back, arms, legs. Sometimes itchy. Pink scaly patches with raised borders. Virus.
Athlete's foot Feet. Itchy, burning. Redness, sometimes with blisters or sores. Fungus.
Eczema and psoriasis tend to be itchy.
Eczema and psoriasis tend to be itchy.

Videos

Video 1 — Close ups of chickenpox on a child.

Video 2 — Information about how shingles develops.

Video 3 — Information about lichen planus.

Video 4 — Information about pityriasis rosea.

Video 5 — Information about psoriasis with pictures.

Additional Resources

www.mayoclinic.com — A slideshow of common skin rashes with pictures and descriptions.

www.webmd.com — Another slideshow of common skin rashes and skin conditions.

www.chiff.com — Pictures of common skin rashes and information about treatment options.

Scratching certain types of rashes may cause them to spread to other parts of the body or even to other people.
Scratching certain types of rashes may cause them to spread to other parts of the body or even to other people.
Mary McMahon
Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a wiseGEEK researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

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Discussion Comments

anon991248

My rash-like spots are on my torso, calves, thighs and butt. They developed about a week ago out of the blue and don't seem to be going away, but they aren't really changing or getting bigger either. They just pop up and stay the same. They are a little smaller than a dime, are slightly raised, feel bumpy when I run my hand over them and are slightly yellowish with tiny red dots. They do not itch and are not painful. Also, there is no fluid or pus inside. They kind of have a shiny surface.

Right now, I've counted about 14 of these patches. It is probably a common skin rash, but since I have a history of anxiety attacks, I automatically assume the worst case scenario and start freaking myself out like, "I just know I have skin cancer! I'm dying! Mayday, Mayday!" I have not told my doctor about this because I feel so stupid and am afraid he will laugh in my face and tell me I'm being paranoid. This is very overwhelming for me. I almost can't handle the anxiety and worried feeling I have right now.

anon925161

For the past three or four months, I've had a minor rash on my chest, moving to my shoulders and partway down my back. Within the past month, it's gone to my legs as well. It is filled with a creamy, white/yellow pus and no doctor can tell me what it is! I've tried $100 creams and stuff, but it doesn't work. It's just really embarrassing, even though it isn't too too bad, I guess.

shanihila

I'm from Israel and I've been traveling in Boulder CO for the last two weeks. I've been itchy all over my body, with red dots everywhere -- a huge rash.

I was hiking and swimming in some hot springs but I don't think it's swimmers itch because it appeared two days after I came back home. Anyway, I don't know what to do. I'm taking some antihistamine pills and using the benedryl ointment. What can it be? These things don't help.

anon288333

I have an itchy spot on my breast with a rash and a little fluid in it.

anon286717

I have a constant red rash on my anus and my groin area. The groin area does not bother me as it does not itch. I use Dovobet daily on my anus area and while it appears to contain the rash it does not clear it. Any suggestions?

anon84881

It might be a heat rash. Why don't you try taking cold showers and instead of wiping your arm dry, allow it to air dry? If this doesn't work, try some petroleum jelly application on your arm after bathing. It helps retain the moisture.

berty

I have a dry spot on my left arm that seems to get worse when expose to the sun. It itches and gets irritated from constantly scratching. I've seen a dermatologist for it, the god news is that it's not cancerous. I can't seem to get rid of it. I've tried lotions and different Ointments; nothing seems to work. Does anyone have any suggestions?

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