What Is This Rash?

Rash is the general term for a change in skin color or texture, often punctuated by itchiness, bumpiness, scaliness, or other discomfort. Rashes result from many different triggers. And many are common, mild, and resolve on their own.

But that might feel like little consolation if you’re currently suffering with a painful, itchy, and mysterious rash that just won’t quit. Scouring the internet for information will lead you to some graphic pictures and dubious feedback on message boards… and that probably won’t help.

To get you the answers you need, we turned to Northwell Health dermatologist Nika Finelt, MD. Here are her tips for how to prevent rashes, how to treat them if they do happen, and when you should see a doctor to evaluate your rash.

Why do rashes occur?

Rashes occur for “a plethora of reasons,” Finelt explains. Most commonly, they happen as a result of skin irritation and dryness. For example, many people suffer from dry skin in the winter, which may also be accompanied by rash.

In addition—and especially lately—we expose our hands to frequent washing and sanitizing with alcohol-based antibacterial gel. This can cause them to become dry, cracked, and painful, and can compromise the skin barrier, meaning that “certain irritants and allergens may enter through our skin and cause even more irritation.”

Finelt adds that soaps, detergents, cooking ingredients, ingredients used to make slime for kids’ projects—just about anything you can think of that your hands get immersed in can cause an irritant effect. And that means that anyone's hands with enough exposure are susceptible to rash.

Who’s most likely to develop a rash?

“Anyone can get a rash at any point in their lives,” Finelt explains, including people of all ages and skin types.

• People with sensitive skin are particularly susceptible to rashes, causing reactions like eczema.
• Rashes can also occur because of inflammation in the skin, such as with psoriasis and other conditions.
• Exposure to allergens like fragrances or chemicals can cause allergic people to break out in a rash.
• Rashes can result from viral, bacterial, or fungal infections.
• And sometimes, rashes can also show up for no known reason at all (the bad news) and resolve fully on their own (the good news).

What are some of the most common types of rashes?

• Contact dermatitis happens after you make contact with an allergen—for instance, a reaction to a new laundry detergent or hand soap. This can cause itching, scaling, and redness, and happens within days or less of the contact.
• Diaper rash is found in babies and toddlers as a result of sustained contact with moisture from a diaper in the thigh, buttocks, and genital area.
• Eczema causes skin to be red, itchy, or scaly, even causing blisters in more severe cases. It’s often found in the extremities and can be exacerbated by seasonal changes.
• Hand, foot, and mouth disease is often found in kids under 5 and is highly contagious, spreading easily within day care or school environments. It causes blisters in the mouth, and red spots on the hands, feet, or genital area.
• Hives are raised red, pink, or flesh-colored welts that hurt. They can be caused by an allergic reaction to medicine, food, or environmental factors.
• Impetigo appears as rash and blisters often around the nose and mouth. It’s most common in babies and kids.
• Psoriasis shows up commonly on the scalp, knees, elbows, and lower back. It appears as scaly patches that may itch.
• Rosacea, which causes facial redness, dryness, and sensitivity, is a chronic condition that appears and fades over time. Stress, alcohol consumption, sun exposure, and other triggers can bring about reappearance.
• Shingles appears as a linear pattern, most often on the torso. It can be extremely painful and include blisters that pop and weep fluid.

How can you prevent rashes?

Avoiding common allergens such as fragranced cleansers and creams is a good first step in preventing rashes, Finelt says. In the winter months when skin tends to be dryer, make sure showers are not too long or too hot. She also suggests using gentle cleansers and bland moistuizers to minimize skin irritation and dryness as a general practice aimed at preventing rashes before they happen.

When should you go to the doctor for a rash?

Some rashes resolve all on their own. Some are mild, common, and easily treated using over-the-counter therapies. “Rashes are treated in different ways depending on the underlying cause,” Finelt says.

But if you have a rash you can’t identify and that doesn’t resolve, seek professional help. Additionally, “If you have a rash that is spreading rapidly or that is causing you discomfort, it is very important that you contact your doctor,” she explains.

Doing so becomes urgent if you feel you are experiencing a severe reaction, such as with anaphylaxis. “If you are worried that you are having a severe allergic reaction accompanied by hives, facial swelling, and the feeling that your throat is starting to close up,” Finelt explains, “then seek medical care right away and get to the nearest emergency room.”

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