What Are Hives?
Hives are pink or red bumps or slightly raised patches of skin.
Sometimes, they have a pale center. Hives usually itch, but they also can burn or
sting.
Hives can happen anywhere on the body. They can be tiny or as big as a dinner plate.
The spots also might look like rings or groups of rings joined together in clusters.
Hives can change locations in a matter of hours. A bunch of hives might be on a
person's face, then go away. Later, more may appear on the person's arms.
Hives are common and usually harmless. But occasionally they're a sign of a serious
allergic reaction. So, always tell your mom or dad if you get them.
The medical term for hives is urticaria (say: ur-tuh-KAR-ee-uh).
When a person is exposed to something that can trigger hives, certain cells in the
body release histamine (say: HIS-tuh-meen) and other substances.
This causes fluid to leak from the small blood vessels under the skin. When this fluid
collects under the skin, it forms the blotches, which we call hives.
Why Do I Get Hives?
People can get hives for lots of different reasons (though sometimes, the cause
is not known).
One common reason for getting hives is an allergic
reaction. Some common allergic triggers are certain foods
(like milk, wheat, eggs, shellfish, berries, and nuts),
medicines (such as antibiotics),
and insect stings or bites.
Other causes of hives are not related to allergies and these can include:
- exposure to the cold (like diving into a cold pool)
- exercise
- sun exposure
- nervousness or stress
- infections caused by viruses
No matter what the cause, a case of hives can last for a few minutes, a few hours,
or even days.