What Are Hives? Symptoms, Causes, Diagnosis, Treatment, and Prevention

What Are Hives? Symptoms, Causes, Diagnosis, Treatment, and Prevention
If you’ve never experienced a bout of hives, consider yourself lucky. Roughly 20 percent of people do get hives at some point in their lives, making it a very common ailment. (1) Hives can be a source of physical and mental anguish, especially if they appear frequently and continue happening for months or years.
What’s important to know is that hives can affect anyone. While some people may carry a higher risk for hives, you can get them no matter your age or gender. Here’s what you should know about the common condition, including why you get hives, how to deal with them if you do, and how to prevent them from coming again (or in the first place).
Signs and Symptoms of Hives
Hives, formally known in the medical community as urticaria, usually appear as red or skin-colored bumps or welts that have defined edges. They can be as small as a pen tip or as large as a dinner plate, and when you press the center of a hive that’s red, it can turn white, something referred to as blanching. (1) They can appear as one hive or show up as blotches or connected patches. And they show up to help control the body’s allergic response to certain triggers.
Hives can be quite itchy, not to mention irritating. While they bring an obvious physical burden, they can hinder emotional well-being too, often isolating individuals socially and affecting performance at work and school, especially if a person has been struggling with hives for a long time, says Sarina Elmariah, MD, PhD, a board-certified dermatologist at Massachusetts General Hospital in Boston.
As you may suspect, hives are easily confused with other conditions, but there are a few characteristics that distinguish them. “Although many conditions can look like hives, they often don’t behave like hives,” says Adam Friedman, MD, professor of dermatology at the George Washington University School of Medicine and Health Sciences in Washington, D.C.
Namely, how long they last and how much they move can help you determine if a rash or skin condition is hives. Common symptoms of hives are: (2)
Red or skin-colored bumps or welts with clear edges that typically clear up within 24 hours, but may reappear in another spot
Bumps or welts that show up either alone or clumped together, covering a larger area
Itchiness around the bumps or welts
Swelling around the bumps or welts
Sometimes pain or stinging at the site of the bumps or welts
If hives last for six weeks or longer, you may be dealing with chronic hives, which can be a sign that something else is going on. (For more information about chronic hives, see below.)
Causes and Risk Factors of Hives
Although hives can have many causes, they all get their start when immune cells in your body called mast cells are activated. In many cases, those mast cells release a chemical called histamine that can cause swelling, itching, and redness. Although not all hives are the result of histamine being released, the vast majority are, Dr. Elmariah says. Here’s the real question, though: What’s causing those mast cells to react in the first place?
That’s a relatively easy question to answer if you have acute hives. “We can generally identify about 50 percent of the triggers after taking a good history of the patient and getting the full story behind the incident,” Dr. Friedman says.
Chronic hives, however, often have different outcomes, and unfortunately, although about 50 percent of hive cases will be resolved within a year of entering the chronic phase, some people will have hives their entire life. “With chronic hives, we can rarely identify why they’re happening, and the longer somebody has hives, the less likely it is that they’ll go away,” says Friedman, adding that 20 percent can continue for longer than 10 years.
Causes for hives are numerous and can be separated by allergic reactions and nonallergic reactions. Hive-inducing allergens include food, medications, insect bites and stings, pollen, animals, touching something you’re allergic to (think latex, for instance), and even allergy shots, according to the American Academy of Dermatology. (3) People who suffer from hives are advised against taking certain medications, such as aspirin or NSAIDs, as these medications can worsen hives. (4)Tap the p.hoto to v.iew the full r.ecipe.