Urticaria is a common skin condition that affects about one in five people at some point in their lives. It leads to intensely itchy, raised areas on the skin called weals or hives, which can be circular or ring-shaped and sometimes merge together.
These patches often develop after scratching and can appear anywhere on the body.
The condition occurs when certain cells in the body, called mast cells, release histamine and other chemical substances into the bloodstream. This causes fluid to leak from the skin’s tiny blood vessels, resulting in the characteristic welts.
While hives typically fade within 24 hours, the underlying condition can take longer to resolve. Urticaria is often accompanied by deeper swelling beneath the skin, known as angioedema. This usually affects softer areas of the body, such as the lips, eyelids, or inside the mouth.
Unlike hives, angioedema takes longer to subside and tends to be more painful than itchy.
If angioedema occurs without the presence of hives, it may be a hereditary form called hereditary angioedema. In these cases, it is not related to urticaria and requires a different approach, including specialized treatment and blood tests for proper diagnosis.
Urticaria can be classified based on how long it lasts:
- Acute Urticaria — the most common type, usually triggered by a known cause, and typically lasting up to six weeks.
- Chronic Urticaria — when outbreaks continue for more than six weeks, often without an identifiable cause.
- Physical Urticaria — triggered by physical factors such as scratching, cold exposure, prolonged pressure on the skin, sunlight, or an increase in body temperature.
Some of the most common causes include allergic reactions, bacterial or viral infections, and emotional stress.
Most hives clear up on their own within 24 hours and often don’t require treatment. However, if the condition persists, a doctor may recommend antihistamines, steroid tablets, or menthol creams to help relieve itching.
People with allergies are more prone to developing hives. They can also appear after taking certain medications or coming into contact with allergens you might not be aware of—such as specific foods, pollen, or environmental triggers. Additionally, when your body is under stress or dealing with another illness, it may become more sensitive, making hives more likely to occur.
