These welts, also called wheals, may be red, pink, white, or skin-colored. Just as they vary in color, hives come in many shapes. Some appear as tiny spots or blotches. Others look like thin, raised lines.
Hives also show up on the skin in many sizes. They can be as small as a pinprick, large as a dinner plate, or any size in between. Regardless of what they look like, hives tend to appear and clear within a few hours.
Some people have one flare-up and never get hives again. If you continue to get hives daily or almost every day for six weeks or longer, you have chronic hives. When you have chronic hives, the most effective treatment often depends on the type of the hives you have and your medical history. Make an appointment to see a board-certified dermatologist, allergist, or primary care doctor.
A thorough medical exam can help rule out possible causes, such as an infection or medication, which could be causing your hives. If signs indicate that this may be the cause, medical testing can find or rule out these causes. While medications and medical conditions can cause hives, there are many other causes, including foods, insect bites, and pressure on the skin. If that happens, your dermatologist can still recommend lifestyle changes and prescribe medication that can help reduce your flare-ups.
Keep track of your flare-ups. Some triggers that can cause long-lasting hives are shown below. Take photos of your hives. When your see your dermatologist, you may not have hives. Taking pictures can help your dermatologist make sure you have hives. Other skin conditions can look like hives. Relieve the itch at home. Itch is common in people who have chronic hives. Who gets them? What causes them? Hives can be caused by many things, including: Colds Bladder infections or other types of infection Allergies to food, particles in the air, or things that touch your skin Insect stings or bites Medicines Heat, cold, or pressure Exercise A serious disease, but this is rare In many cases, no specific cause is found.
How are they diagnosed? How are they treated? Where can I get more information? Read the full article. Get immediate access, anytime, anywhere. Choose a single article, issue, or full-access subscription.
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Navigate this Article. But the good news is that many people eventually outgrow these allergies. If you like being outdoors, try to wear long-sleeved clothes and long pants to avoid insect bites. Keep food covered to prevent attracting bees or wasps.
Wear closed-toe shoes and avoid clothing that could trap a stinging insect when outdoors. After an outbreak of hives has gone away, avoid wearing tight-fitting clothing and stay away from hot baths or showers for a while. Both can cause the hives to return. If the hives persist, get a thorough medical evaluation. There are some rare immune disorders that can cause hives, but only a comprehensive exam can determine that. If you have hives that linger for six weeks or more, ask your primary care doctor for advice.
He or she may refer you to a specialist such as an allergist or immunologist. They can do skin or blood tests to help determine what foods or other substances trigger your hives.
American Academy of Allergy, Asthma and Immunology. Tips to Remember: Allergic Skin Conditions. Mayo Clinic. Hives and angioedema. Common Food Allergens. MedlinePlus, National Institutes of Health. Medical Encyclopedia: Hives.
Insect Bites and Stings. University of Chicago Hospitals. Bee Stings. Hives and Angioedema. Usatine RP. Prostatitis and pruritus caused by a drug allergy; photo rounds urticaria hives. Journal of Family Practice. Carroccio A, et al. Evidence of very delayed clinical reactions to cows milk in cows milk-intolerant patients. June, ;55 6 American Osteopathic College of Dermatology. Urticaria Hives. Asthma and Allergy Foundation of America.
Other people find that cold temperatures, sunlight or friction trigger an outbreak, and in some rare cases, water can also be a trigger for hives. If you have physical urticaria, your hives will normally develop within minutes, and then fade within 1 hour. If you think that you may have this form of hives, try to identify your triggers and avoid them as much as you can.
You may also find that it helps to take an antihistamine when you break out in a rash, but you should see a doctor if you intend to take antihistamine medications for more than a couple of days in a row. You should see a doctor if your symptoms do not improve after 2 days, your rash seems to be getting worse or your hives keep going away and then coming back, as this could be a sign that you are allergic to something.
You should also see a doctor if you have a high temperature or notice any swelling under your skin angioedema. We include references at the end of every article, so you know where we get our facts. When we talk about popular health trends or claims, we'll always tell you if there's very little or no evidence to back them up.
Our medical team also checks our sources, making sure they're appropriate and that we've interpreted the science correctly. Erythema multiforme is a skin reaction usually mild caused by an allergy or infection.
Rosacea is a common but poorly understood long-term chronic skin condition that mainly affects the face. Symptoms begin with episodes of flushing w Granuloma annulare is a rash that looks like a ring of small bumps.
It usually affects only 1 to 2 areas, but in rare cases, it can be more widespread
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