Urticaria, commonly known as hives, is a skin condition characterized by the sudden appearance of red, itchy welts or bumps on the skin. These welts can vary in size and shape, and they often merge to form larger areas of swelling. Urticaria can be acute (lasting less than six weeks) or chronic (lasting more than six weeks), and it can be triggered by a variety of factors.
Symptoms of Urticaria:
- Red or Skin-Colored Welts: These welts can appear anywhere on the body, including the face, lips, tongue, throat, and ears. They may range in size from small spots to large patches.
- Itching: The welts are often intensely itchy, though some people experience a burning or stinging sensation instead.
- Swelling: Swelling, or angioedema, can occur deeper in the skin, particularly around the eyes, lips, or throat. This can be more serious if it interferes with breathing.
- Welts That Change Shape or Disappear: The welts may move around the body, disappear, and reappear elsewhere within a few hours.
Causes and Triggers:
- Allergic Reactions:
- Food: Common food allergens include nuts, shellfish, eggs, and milk.
- Medications: Antibiotics (e.g., penicillin), NSAIDs (e.g., aspirin, ibuprofen), and certain other drugs can trigger hives.
- Insect Stings or Bites: Reactions to bee stings, mosquito bites, or other insects can cause hives.
- Latex: Some people develop hives after contact with latex.
- Physical Triggers:
- Pressure: Prolonged pressure on the skin, such as from tight clothing or sitting for a long time, can cause hives.
- Temperature Extremes: Exposure to cold (cold urticaria) or heat can trigger hives in some individuals.
- Sunlight: Solar urticaria is triggered by exposure to the sun.
- Water: Rarely, contact with water (aquagenic urticaria) can cause hives.
- Infections:
- Viral Infections: Such as the common cold, hepatitis, or mononucleosis.
- Bacterial Infections: Like strep throat or urinary tract infections.
- Fungal Infections: Can also trigger hives in some cases.
- Stress: Emotional stress can exacerbate urticaria in susceptible individuals.
- Chronic Illness: Conditions such as thyroid disease, lupus, or vasculitis can be associated with chronic hives.
- Idiopathic: In many cases, particularly in chronic urticaria, the exact cause may not be identifiable (idiopathic urticaria).
Diagnosis:
- Medical History and Physical Examination: A doctor will examine the hives and ask about possible triggers, recent exposures, and any associated symptoms.
- Allergy Testing: Skin prick tests or blood tests may be done to identify specific allergens.
- Blood Tests: To check for underlying conditions like thyroid disease or infections.
- Skin Biopsy: Rarely, a skin biopsy may be performed if the diagnosis is unclear or to rule out other conditions.
While most cases of urticaria are not serious and can be managed with proper treatment, chronic or severe hives may require ongoing medical care to manage symptoms and prevent complications.