Summary about Disease
Urticaria (hives) is a skin condition characterized by raised, itchy welts (wheals) that appear on the skin. Angioedema is swelling in the deeper layers of the skin, often occurring with urticaria. Both conditions are usually triggered by an allergic reaction, but other causes are possible. The conditions can resolve quickly or become chronic, lasting for longer than six weeks.
Symptoms
Urticaria (Hives):
Itchy, raised welts (wheals) that can be small or large.
Welts can be round, oval, or irregularly shaped.
Welts may appear and disappear quickly, moving to different areas of the skin.
Blanching (turning white) when pressed.
Angioedema:
Deep swelling, often around the eyes, lips, tongue, genitals, hands, and feet.
Swelling can be painful.
Difficulty breathing or swallowing (if the throat is involved).
Causes
Allergic Reactions: Foods (e.g., peanuts, shellfish, eggs), medications (e.g., penicillin, aspirin, NSAIDs), insect stings, latex.
Non-Allergic Causes: Infections (viral, bacterial, fungal), physical stimuli (pressure, cold, heat, sunlight, vibration), stress, exercise, autoimmune diseases, certain medical conditions (e.g., thyroid disease, lymphoma), and rarely, genetic factors.
Idiopathic: In many cases, the cause cannot be identified (chronic idiopathic urticaria).
Medicine Used
Antihistamines: These are the first-line treatment to relieve itching and reduce the appearance of hives. Examples include cetirizine, loratadine, fexofenadine (non-drowsy options) and diphenhydramine (can cause drowsiness).
H2 Antihistamines: Ranitidine or famotidine are sometimes combined with H1 antihistamines for more effective relief.
Corticosteroids: Oral corticosteroids (e.g., prednisone) may be prescribed for severe outbreaks to reduce inflammation. They are typically used for short periods due to potential side effects.
Epinephrine: For severe allergic reactions (anaphylaxis) with angioedema affecting breathing, an epinephrine auto-injector (EpiPen) is used.
Omalizumab: An injectable monoclonal antibody medication used for chronic idiopathic urticaria that is resistant to antihistamines.
Other Medications: Leukotriene receptor antagonists (e.g., montelukast) and immunosuppressants (e.g., cyclosporine) may be used in some cases.
Is Communicable
Urticaria and angioedema are not communicable. They are not contagious and cannot be spread from person to person.
Precautions
Identify and Avoid Triggers: If the trigger is known (e.g., a specific food), strictly avoid it.
Carry Emergency Medication: If you have a history of severe allergic reactions, carry an epinephrine auto-injector and know how to use it.
Avoid Irritants: Wear loose-fitting clothing, avoid harsh soaps and detergents, and protect your skin from extreme temperatures and sunlight.
Manage Stress: Stress can worsen urticaria, so practice stress-reduction techniques.
Medical Alert: Consider wearing a medical alert bracelet or necklace to inform others about your allergies or condition.
How long does an outbreak last?
Acute Urticaria/Angioedema: Outbreaks last less than six weeks and often resolve within a few hours to a few days.
Chronic Urticaria/Angioedema: Outbreaks last longer than six weeks and can persist for months or even years. Symptoms may come and go.
How is it diagnosed?
Medical History: The doctor will ask about your symptoms, potential triggers, medical history, and family history of allergies or urticaria/angioedema.
Physical Examination: The doctor will examine your skin for hives and swelling.
Allergy Testing: Skin prick tests or blood tests (RAST or ImmunoCAP) may be performed to identify specific allergens.
Blood Tests: Complete blood count (CBC), erythrocyte sedimentation rate (ESR), or C-reactive protein (CRP) may be ordered to look for signs of infection or inflammation.
Skin Biopsy: In rare cases, a skin biopsy may be performed to rule out other conditions.
Timeline of Symptoms
The timeline can vary greatly depending on the cause and individual.
Immediate Reaction: Symptoms appear within minutes to hours after exposure to a trigger (e.g., allergic reaction).
Delayed Reaction: Symptoms appear several hours or even days after exposure to a trigger (e.g., some medications).
Chronic Urticaria: Symptoms can appear spontaneously and persist for weeks, months, or years, with periods of remission and flare-ups.
Angioedema: Swelling can develop rapidly, peaking within hours, and may take several days to resolve.
Important Considerations
Anaphylaxis: Angioedema, especially if it affects the throat, can be life-threatening. Seek immediate medical attention if you have difficulty breathing or swallowing.
Chronic Urticaria: Finding the underlying cause of chronic urticaria can be challenging.
Medication Side Effects: Be aware of the potential side effects of medications used to treat urticaria and angioedema, especially corticosteroids.
Pregnancy and Breastfeeding: Some medications for urticaria and angioedema are not safe during pregnancy or breastfeeding. Consult your doctor about appropriate treatment options.
Quality of Life: Chronic urticaria can significantly impact quality of life. Seek support from healthcare professionals and support groups.