What are Hives?

Hives are a common skin condition that causes raised, itchy patches to appear suddenly. These areas can be red or match your skin tone and may change shape or location throughout the day. In many cases, each spot fades within a few hours, but new ones can appear.

Hives can be caused by:

• Food allergies, including nuts, eggs, fish, shellfish, milk, wheat, or soy
• Medications like antibiotics or anti-inflammatory drugs
• Viral infections
• Physical triggers such as cold, heat, pressure, sunlight, or exercise
• Stress or environmental exposures like pet dander or latex

Sometimes, hives develop without a clear reason, especially when they last for several weeks.

Symptoms

Hives often come on quickly, may be uncomfortable, but are usually not dangerous. They can be triggered by many different factors.

Common symptoms include:

• Itchy, raised welts on the skin
• Red or pale patches with defined edges
• Spots that move, grow, or disappear within hours
• Swelling in certain areas, such as the lips or eyelids

How are Hives Diagnosed?

A healthcare provider can often recognize hives by examining your skin and asking about your symptoms. They may ask about recent foods, medications, or exposures.

If a trigger isn’t obvious, additional testing may include:

• Allergy testing with blood or skin samples
• Rarely, a small skin sample (biopsy) is taken to rule out other conditions

How are Hives Treated?

Many cases of hives improve on their own, especially when the trigger is removed. Treatment focuses on relieving symptoms and preventing flare-ups.

Common treatment options include:

• Avoiding known triggers
• Antihistamines to reduce itching and swelling
• Short-term steroid medications for more severe symptoms
• Advanced therapies, such as biologic injections, for chronic or difficult cases

If swelling occurs deeper in the skin—especially around the throat or tongue—it may require emergency care.