Hives vs. rash: How to tell the difference - Insider

• Hives are a type of rash that results from an allergic reaction, insect bite, infection, and more.
• You can identify hives by pressing down on the bump — if it turns white, it's a hive.
• You should see a doctor immediately if your hives are accompanied by difficulty swallowing

Most people will deal with some kind of skin rash or irritation at some point in their lives. There are many different types of skin rashes you might experience with different causes and courses of treatment. 

It can be challenging to tell the difference between varioustypes of rashes, but understanding the type of rash you are dealing with can help you better treat it and reduce symptoms, like itching and swelling.

Hives, or urticaria, are a particular type of rash that may require different treatment than other types of rashes. Here's how to tell the difference between hives and other rashes as well as common causes of skin irritation and how to treat them. 

How to tell the difference between hives and a rash

A skin rash is generally defined as any kind of irritation or swelling of the skin. There are thousands of different conditions that can affect the skin and cause different types of rashes with different types of symptoms, says Dr. Kellie Reed, a board-certified dermatologist with Westlake Dermatology.

Hives, on the other hand, are a type of rash that has a distinct set of symptoms. Unlike most rashes, hives:

• Have "blanching": This means that pressing a hive makes it turn white.
• Change location: The bumps may disappear and reappear on another part of the body relatively quickly. 
• Change shape: Hives appear as irregular wheals that often change shape and appearance. The raised itchy bumps that come with hives distinguish it from other types of skin rashes, says Dr. Viktoryia D. Kazlouskaya, an assistant professor in the department of dermatology at the University of Pittsburgh. 
• Are not scaly: Unlike other types of rashes, which may appear dry and blistered, hives are not scaly.

Hives can develop anywhere on the body, but most commonly appear on the chest, neck, arms, and legs. 

If you have hives

Hives can have a few different causes, including:

• Environmental allergens, like tree and grass pollen, mold, or pet dander. 
• Food allergies to milk, peanuts, eggs, and shellfish. 
• An allergic reaction to a medication, like penicillin, aspirin, or ibuprofen. 
• Bacterial infections, like strep throat
• Insect bites
• Stress
• A sudden change in body temperature

In most cases hives are acute, meaning they come on suddenly, are tied to a particular trigger or allergen, and typically resolve within a few days. In more severe cases, hives may be chronic, persisting for six weeks or longer without an obvious cause. 

Acute hives can often be treated at home with over-the-counter medications and at-home remedies. Here are some ways to find relief:

• Apply a cool, wet compress to relieve itching and swelling
• Take an over-the-counter antihistamine, like Zyrtec or Claritin
• Spread an anti-itch cream, like Coritzone, or lotion, like calamine lotion on the affected area 
• Soak in a lukewarm bath and avoid scrubbing your skin with a washcloth or loofah. Instead, gently apply gentle, fragrance-free soap with your hands.

Chronic hives that persist for weeks may require a different course of treatment. Options include:

• A prescription corticosteroid, like prednisone. This can reduce inflammation and relieve itching.
• A prescription injectable medication called Omalizumab. This drug works by blocking substances in the body that cause hives and is often recommended when antihistamines fail to resolve symptoms. 
• Light therapy. Also called phototherapy, this treatment requires several trips a week over the course of a few months to a dermatologist or phototherapy treatment center. Light therapy uses UV rays to slow the rapid growth of skin cells that may be contributing to chronic hives. 

Important: In some cases, hives can be a sign of a life-threatening allergic reaction known as anaphylaxis. Seek immediate medical care or go to your nearest emergency room if you are experiencing hives in addition to:

• A racing heartbeat
• Swelling in your mouth or throat
• Difficulty swallowing
• Feeling light-headed or dizzy

If you have a rash

There are many types of skin rashes with many different causes and symptoms. Some of the most common ones include:

• Irritant contact dermatitis: This type of rash is caused by contact with an irritant, like chemicals, fragrances, or certain types of soaps or lotions. Irritant contact dermatitis can cause redness, swelling, and itchiness. 
• Allergic contact dermatitis: You might develop this type of rash if you come into contact with a substance you are allergic to, like latex, hair dye, or jewelry made of nickel. Contact with poison ivy can also cause this type of rash which may produce red, scaly, and crusty patches on your skin. 
• Eczema: Also known as atopic dermatitis, eczema is an inflammatory condition that can cause dry, chapped, itchy, and bumpy patches on the skin that may become red and swollen.
• Psoriasis: Psoriasis is a chronic autoimmune disease that causes a rapid buildup of skin cells that form scaly plaques that are often itchy and uncomfortable.

Eczema and psoriasis tend to be more chronic and may wax and wane throughout life, Reed says, while other types of rashes, like irritant contact dermatitis, are often resolved once you know the trigger and can avoid it. 

Skin rash treatments

The right course of treatment for you will depend on the type of rash you're dealing with and its causes.

Generally speaking, some treatments options for the most common kinds of rashes include:

• Topical steroids: These are creams or gels that can be applied to the rash to soothe itching and swelling, Reed says. You can find over-the-counter options, like hydrocortisone cream, at drug stores and pharmacies. Your doctor may also suggest a stronger prescription option if an over-the-counter topical steroid does not resolve your symptoms. 
• Oral medications: If your rash is more severe, your doctor may prescribe an oral corticosteroid to reduce inflammation or an antihistamine to relieve itching.
• Biologics: For more chronic conditions that can cause rashes, like psoriasis, some drugs, known as biologics, can help manage symptoms and prevent flare-ups. Biologic treatments are injections that target the overactive parts of the immune system that cause psoriasis symptoms.

Other remedies like soaking in a lukewarm bath or applying a cool, wet compress to the affected area may also help soothe mild rashes.

If you experience frequent rashes, talk with your doctor who can provide you with a list of common irritants and allergens that may be contributing to your symptoms. Once you identify the triggers of your rashes, you can take steps to avoid them and reduce your symptoms.

Insider's takeaway

A skin rash is any kind of irritation or inflammation of the skin that may cause many different symptoms, including redness, itching, and swelling. There are many different types of skin rashes, each with different causes.

Hives are a type of skin rash that cause itchy raised bumps on the skin. They are most often the result of some kind of irritating trigger in the environment, like an allergen, but can also occur in response to stress or sudden changes in body temperature.

Acute hives that resolve within a few days can be treated at home with over-the-counter antihistamines and at-home remedies. Chronic hives that persist for weeks require an evaluation from a dermatologist and a different course of treatment which may include prescription medications or therapies.

Erin Heger