Hives (Urticaria): Causes, Symptoms, and Treatment

Hives are raised, itchy welts on the skin that can appear suddenly and are often triggered by an allergic reaction or other factors. Most cases are temporary and resolve on their own, but some may require medical treatment.

In plain words

Hives are itchy, raised bumps on the skin that appear suddenly. They can be small or large, and may change shape or move around. Hives usually go away within a day but may come back. They are not contagious. Common causes include allergies to food or medicine, infections, stress, or reactions to heat or cold. Most hives are harmless but annoying. If hives last more than 6 weeks, they are called chronic hives. Some people get hives along with swelling of the face, lips, or throat, which can be serious.

What is Hives (Urticaria): Causes, Symptoms, and Treatment?

Hives are raised, itchy welts on the skin that can appear suddenly and are often triggered by an allergic reaction or other factors. Most cases are temporary and resolve on their own, but some may require medical treatment.

Symptoms

Early symptoms

  • Raised, red welts: Hives appear as raised, red welts on the skin. They can vary in size from small spots to large patches and may merge together. (1) (2)
  • Itching: The welts are often intensely itchy, which can cause discomfort and disrupt daily activities. (1) (3)
  • Burning or stinging sensation: Some people experience a burning or stinging feeling in the affected areas, especially if the hives are widespread. (2)
  • Rapidly changing appearance: Hives can change shape, size, and location quickly, often disappearing and reappearing in different areas. (1) (3)

Serious or emergency symptoms

  • Swelling of the face or throat (angioedema): Severe swelling of the lips, eyelids, or throat can occur alongside hives and may indicate a serious allergic reaction. Seek emergency medical attention immediately. (2) (6)
  • Difficulty breathing: If hives are accompanied by difficulty breathing, it could be a sign of anaphylaxis, a life-threatening condition. Call emergency services immediately. (2) (6)

Causes

Primary causes

  • Allergic reactions: Common allergens such as food, medications, insect stings, or latex can trigger hives by causing the release of histamine. (1) (2)
  • Infections: Viral or bacterial infections, such as the common cold or urinary tract infections, can lead to hives. (2) (4)
  • Physical triggers: Temperature changes, pressure on the skin, sunlight, or exercise can cause hives in some people. (2) (1)
  • Stress: Emotional stress can trigger hives in some individuals, especially those with a history of chronic urticaria. (2)

Risk factors

History of allergies

People with a history of allergies or asthma are more likely to develop hives. (2) (4)

Family history of urticaria

A family history of hives or other allergic conditions increases the risk. (2)

Stressful lifestyle

High stress levels can trigger hives, especially in individuals prone to chronic urticaria. (2)

Diagnosis

A doctor can diagnose hives by examining the skin and discussing symptoms and medical history. Tests may be ordered to identify triggers, such as allergy testing or blood work. Chronic hives may require more extensive testing to rule out underlying conditions.

Skin examination

The doctor will look for raised, red welts and assess their size, shape, and distribution. (5)

Allergy testing

Allergy tests can help identify specific triggers, such as food or environmental allergens. (5)

Blood tests

Blood work may be done to check for infections or other underlying conditions. (5)

Treatment

Medication options

Antihistamines

Antihistamines block the effects of histamine, reducing itching and swelling associated with hives. (1) (5)

Corticosteroids

Corticosteroids reduce inflammation and are used for severe cases of hives that do not respond to antihistamines. (5)

Epinephrine

Epinephrine is used in emergencies to treat severe allergic reactions, such as anaphylaxis, which can accompany hives. (5)

Lifestyle and self-care

  • Avoid known triggers: Identifying and avoiding triggers, such as specific foods, medications, or environmental factors, can help prevent hives. (5)
  • Manage stress: Practicing stress-reduction techniques, such as meditation or yoga, can help reduce the frequency of hives outbreaks. (5)
  • Wear loose clothing: Tight clothing can irritate the skin and worsen hives, so wearing loose, breathable fabrics is recommended. (5)

Always discuss dosing and treatment changes with your own prescriber.

Possible complications

  • Angioedema: Swelling beneath the skin, particularly around the eyes, lips, and throat, can occur alongside hives and may cause discomfort or difficulty breathing. (7)
  • Chronic urticaria: When hives persist for more than six weeks, they are considered chronic and may require long-term treatment. (7)
  • Anaphylaxis: In rare cases, hives can be a symptom of a severe allergic reaction called anaphylaxis, which requires immediate emergency treatment. (7)

When to see a doctor

Routine follow-up

  • If hives persist for more than a few days or recur frequently, consult a doctor to identify potential triggers and discuss treatment options. (1) (4)

Seek emergency care

  • Seek emergency care if hives are accompanied by swelling of the face or throat, difficulty breathing, or dizziness, as these could indicate anaphylaxis. (7) (6)

Frequently asked questions

What causes hives?

Hives are caused by the release of histamine in response to triggers like allergens, infections, stress, or environmental factors. Identifying the specific trigger can help manage and prevent outbreaks. (1) (2)

When should I worry about hives?

Seek medical attention if hives are severe, last more than a few days, or are accompanied by swelling of the face or throat, difficulty breathing, or dizziness. These symptoms could indicate a serious allergic reaction. (6) (7)

Is hives serious?

Most cases of hives are temporary and harmless, but severe or persistent hives can indicate an underlying condition or a serious allergic reaction. (2) (6)

How do I get rid of hives?

Antihistamines are the most effective treatment for relieving hives. Avoiding known triggers and managing stress can also help prevent outbreaks. (5) (1)

When should I see a doctor about hives?

Consult a doctor if hives are severe, last more than a few days, or are accompanied by symptoms like swelling or difficulty breathing. (6) (7)

References

  1. NHS — Hives source 1
  2. Mayo Clinic — Hives and angioedema - Symptoms and causes source 2
  3. MedlinePlus — Hives source 3
  4. CDC — Skin Rashes source 4
  5. Mayo Clinic — Hives and angioedema - Diagnosis and treatment source 5
  6. NHS — When to worry about a rash source 6
  7. Mayo Clinic — Hives and angioedema - Complications source 7