Urticaria
Urticaria, commonly known as hives, is a skin reaction characterized by raised, red, itchy welts (also called wheals) that can appear anywhere on the body. These welts may vary in size and shape, and they often appear suddenly and resolve within hours, though in some cases, they can persist for weeks or longer. Urticaria can be acute (short-term) or chronic (long-lasting).
Types of Urticaria:
- Acute Urticaria:
- Lasts less than 6 weeks.
- Often triggered by an allergen, infection, or other temporary factor.
- Chronic Urticaria:
- Persists for more than 6 weeks, with recurring episodes.
- May not have an identifiable cause and is often considered idiopathic.
- Physical Urticaria:
- Triggered by physical stimuli, such as pressure, cold, heat, sunlight, or vibration.
- Angioedema:
- Swelling of the deeper layers of the skin, often associated with urticaria. It can affect the lips, eyelids, and throat, and in severe cases, it may impair breathing.
Causes and Triggers:
- Allergic Reactions:
- Foods (e.g., nuts, shellfish, eggs)
- Medications (e.g., penicillin, aspirin, NSAIDs)
- Insect stings or bites
- Non-Allergic Triggers:
- Infections (viral, bacterial, or parasitic)
- Physical factors (cold, heat, sunlight, water, pressure)
- Stress or emotional factors
- Hormonal changes
- Exercise-induced urticaria
- Idiopathic: In many chronic cases, no specific cause is identified.
Symptoms:
- Welts (Wheals):
- Raised, red or skin-colored, and often surrounded by a pale halo.
- Can vary in size from small dots to large patches.
- Itching:
- Intense itching is a hallmark symptom, although some may experience burning or stinging.
- Transient Nature:
- Individual hives usually resolve within 24 hours, though new ones may appear elsewhere.
- Angioedema (in some cases):
- Swelling of deeper tissues, particularly around the eyes, lips, hands, feet, or throat.
- Systemic Symptoms (Rare):
- Severe allergic reactions (anaphylaxis) may include difficulty breathing, wheezing, dizziness, or swelling in the throat. This is a medical emergency.
Diagnosis:
- Clinical History:
- Detailed history of symptoms, potential triggers, and any associated factors like medications or recent infections.
- Physical Examination:
- Evaluation of the pattern, location, and duration of hives.
- Allergy Testing:
- Skin prick tests or blood tests (e.g., IgE levels) to identify potential allergens.
- Blood Tests:
- To rule out underlying conditions like autoimmune diseases or infections.
- Challenge Tests:
- For physical urticaria, exposure to the suspected trigger under controlled conditions (e.g., cold, heat, or pressure).
Treatment:
- Antihistamines:
- First-line treatment: Non-sedating antihistamines (e.g., loratadine, cetirizine) are used to block the histamine response.
- In severe cases, sedating antihistamines (e.g., diphenhydramine) may be used.
- Corticosteroids:
- For severe or persistent cases, a short course of oral corticosteroids (e.g., prednisone) may be prescribed.
- Avoiding Triggers:
- Identifying and avoiding known triggers can prevent future episodes.
- Epinephrine (Adrenaline):
- Used in emergencies, such as anaphylaxis, to counteract severe allergic reactions.
- Chronic Urticaria Management:
- Omalizumab (Xolair): An injectable medication for chronic idiopathic urticaria that does not respond to antihistamines.
- Cyclosporine: An immunosuppressant used in refractory cases.
- Lifestyle Adjustments:
- Wearing loose, comfortable clothing.
- Using cooling agents or soothing creams to relieve itching.
Prognosis:
- Acute Urticaria: Usually resolves within hours to weeks and does not recur once the trigger is removed.
- Chronic Urticaria: Can persist for months or years but often resolves over time.
- With appropriate treatment and trigger management, most cases can be effectively controlled.
Southlake Dermatology
Connect With Us
© 2024 Southlake Dermatology. All Rights Reserved. | Sitemap | Privacy Policy | Notice of Privacy Practices | Terms of Service
