Urticaria

Urticaria is a prevalent skin condition that affects millions of people worldwide. It is characterised by the appearance of itchy, raised welts or bumps on the skin, which can cause significant discomfort and distress. While the exact urticaria cause is not always clear, it is often the result of an allergic reaction or an underlying medical condition. In this article, we will explore the causes, symptoms, and management options for urticaria.

What is Urticaria?

Urticaria or hives is a skin condition that occurs when the body's immune system reacts to an allergen or irritant. This reaction triggers mast cells in the skin to release histamine and other chemical mediators. These substances cause the blood vessels to leak fluid into the surrounding tissues, leading to swelling and inflammation. The resulting welts or bumps can appear anywhere on the body and are often itchy and uncomfortable. The triggers for urticaria can vary widely and may include foods, medications, infections, insect bites, or physical stimuli such as cold, heat, or pressure.

Urticaria can be further classified based on its duration, specific triggers, or underlying causes.

1. Physical Urticaria

Physical urticaria, also known as inducible urticaria, is a type of chronic urticaria that is caused by physical stimuli such as cold, heat, sunlight, vibration, pressure, or exercise. The symptoms can appear within minutes to hours after exposure to the trigger. Some common types of physical urticaria include:

• Dermatographism: Hives rash that forms after stroking or scratching the skin.

• Cholinergic Urticaria: Small, itchy bumps that appear within 15 minutes of exercise or physical exertion.

• Solar Urticaria: Hives caused by exposure to sunlight.

• Cold Urticaria: Hives triggered by exposure to cold temperatures.

• Aquagenic Urticaria: Hives triggered by contact with water.

2. Acute Urticaria

Acute urticaria refers to hives that last less than six weeks. It is often caused by an allergic reaction to food, medication, environment, insect bites, or infection. The symptoms can appear suddenly and can be itchy, burning, or stinging.

3. Chronic Urticaria

Chronic urticaria refers to hives that last more than six weeks. It can be spontaneous or inducible and may be caused by chronic infections, autoimmune disorders, or other underlying medical conditions. The symptoms can be persistent and may require ongoing hives treatment. It is further divided into two subtypes:

• Chronic Spontaneous Urticaria (CSU): This subtype occurs without any identifiable cause and can appear at any time.

• Chronic Inducible Urticaria (CIndU): It is a subtype of chronic urticaria that is triggered by specific stimuli. These triggers can include pressure, heat, cold, sunlight, vibration, or even emotional stress. Symptoms often appear within minutes to hours after exposure to the trigger and may persist for several hours or days.

Urticaria symptoms can vary but typically include:

• Itchy Welts: Raised, itchy patches on the skin that can appear anywhere on the body. These welts can range in size from a few millimetres to several centimetres and typically last less than 24 hours, resolving without leaving any marks or bruising.

• Erythema: Redness around the welts, which can be more pronounced in some cases.

• Angioedema: Swelling of the deeper layers of the skin and mucous membranes, which can be painful rather than itchy. This often occurs in the face, throat, hands, and feet.

• Appearance: Welts can be round, form rings, or create map-like patterns on the skin.

Hives causes are diverse and can include:

• Viral Infections: Viral infections are a common cause of acute urticaria, particularly in children.

• Allergies: Food allergies, medication allergies, and environmental allergies (such as pollen, pet dander, or insect bites) can trigger urticaria.

• Physical Stimuli: As mentioned in the types of urticaria, various physical factors such as cold, heat, pressure, sunlight, and vibration can induce hives.

• Autoimmune Disorders: In some cases, particularly in CSU, the body's immune system mistakenly attacks healthy cells, leading to the release of histamine and other chemicals that cause hives.

• Stress: Emotional stress can worsen or even trigger urticaria in some individuals.

• Certain Medications: Some medications, such as aspirin, non-steroidal anti-inflammatory drugs (NSAIDs), and antibiotics, can cause urticaria as a side effect.

Urticaria can lead to several complications, some of which are severe and require immediate medical attention:

• Anaphylaxis: This is a life-threatening allergic reaction that can occur alongside hives. Symptoms include swelling of the face, mouth, throat, and airways, causing difficulty breathing, wheezing, fast heart rate, clammy skin, anxiety, confusion, dizziness, vomiting, and potentially fainting or loss of consciousness. If these symptoms are present, it is crucial to use an epinephrine auto-injector, if available, and seek emergency medical care immediately.

• Angioedema: This condition involves deep swelling under the skin, often around the eyes, lips, and sometimes the genitals, hands, and feet. Angioedema can be particularly dangerous if it affects the throat, tongue, or lungs, as it can block airways and make breathing difficult.

• Secondary Infections: Scratching the hives can lead to skin infections, which may require additional treatment such as antiseptic creams or antibiotics.

• Impact on Daily Life: Chronic urticaria can significantly interfere with sleep and daily activities due to intense itchiness and discomfort.

Preventing urticaria involves several strategies to minimise exposure to known triggers and manage symptoms:

• Avoid Known Triggers: Keeping a diary to track when hives occur can help pinpoint specific allergens or irritants. If you know what triggers your hives, avoid those substances. Common triggers include certain foods (e.g. nuts, eggs, seafood), medications (e.g. aspirin, NSAIDs), latex, and some plants.

• Use Mild Products: Choose mild or fragrance-free soaps, skin creams, and detergents to reduce skin irritation.

• Manage Stress: Stress can exacerbate hives; using relaxation techniques such as meditation can help manage stress levels.

• Avoid Tight Clothing: Wearing loose, light, cotton clothing can help reduce skin irritation and discomfort and prevent physical urticaria triggered by friction or pressure.

• Cool Environment: Working and sleeping in a cool environment and using cool compresses or wet clothes can help ease itchiness.

• Maintain Good Hygiene: Bathing and changing clothes after exposure to potential allergens like pollen or animal contact can help prevent hives.

Diagnosing urticaria involves a combination of physical examination, medical history review, and sometimes, additional tests. Your doctor will ask about your symptoms, their duration, and any potential triggers you may have identified. They will also examine your skin to assess the appearance and distribution of the hives.

In some cases, your doctor may recommend the following tests to help determine the underlying cause of your urticaria:

• Skin Prick Test: This test involves placing small amounts of potential allergens on your skin and pricking the skin to allow the substance to enter. If you're allergic to a particular substance, a small bump or hive will appear at the test site.

• Blood Tests: These tests can help identify potential infections, hormonal imbalances, or other underlying health conditions that may be causing your urticaria. Specific tests may include a complete blood count (CBC), thyroid function tests, and tests for autoimmune disorders.

• Challenge Tests: In some cases, your doctor may recommend a supervised challenge test, where you are exposed to a suspected trigger, such as a medication or food, to see if it causes a reaction. This test is conducted under close medical supervision to ensure your safety.

• Skin Biopsy: Rarely, a small sample of skin may be removed and examined under a microscope to rule out other skin disorders.

The treatment and management of urticaria depend on the type and severity of the condition. The primary goals are to relieve symptoms, identify and avoid triggers, and prevent recurrences. Here are some common treatment options for urticaria:

• Antihistamines: Second-generation H1 antihistamines, such as loratadine, desloratadine, fexofenadine, cetirizine, and levocetirizine, are the first-line treatment for urticaria. These urticaria medications have fewer side effects, less sedation, and fewer interactions compared to first-generation antihistamines. First-generation antihistamines, such as diphenhydramine, chlorpheniramine, and hydroxyzine, can also be used but are less preferred due to their sedative and anticholinergic effects.

• H2 Antihistamines: In refractory cases, adding H2 antihistamines, such as ranitidine, nizatidine, or famotidine, to H1 antihistamines may be beneficial.

• Systemic Corticosteroids: Short-term use of corticosteroids, such as prednisone or prednisolone, can help control severe symptoms or significant angioedema. However, systemic corticosteroids should be used cautiously, especially in patients with diabetes, hypertension, or osteoporosis, due to potential side effects.

• Leukotriene Receptor Antagonists (LTRAs): LTRAs, such as montelukast, can be useful, particularly in patients with cold urticaria or intolerance to NSAIDs.

• Immunomodulators and Biologics: For chronic urticaria resistant to high-dose antihistamines, cyclosporine can be effective. However, it should be used cautiously due to potential side effects and contraindications, such as impaired kidney function and uncontrolled blood pressure. Omalizumab, a monoclonal antibody against IgE, is effective for CSU that is resistant to high-dose antihistamine therapy.

Living with urticaria can be challenging, as the symptoms can be uncomfortable and unpredictable. Here are some urticaria home remedies to help manage the condition and improve your quality of life:

• Identify and avoid triggers, such as certain foods, medications, or environmental factors, when possible.

• You may get itching relief from urticaria by using cool compresses or taking cool showers.

• Wear loose, lightweight, and breathable clothing to minimise skin irritation.

• Manage stress through relaxation techniques, such as deep breathing, meditation, or yoga.

• Maintain a healthy lifestyle by eating a balanced diet, staying hydrated, getting regular exercise, and getting enough sleep.

• Keep a symptom diary to help identify patterns and potential triggers.

While mild cases of urticaria can often be managed at home with over-the-counter antihistamines, there are certain situations when it is important to seek medical attention:

• If your symptoms are severe or widespread, causing significant discomfort or interfering with your daily activities.

• If you experience difficulty breathing, wheezing, or swelling of the tongue, lips, or throat, as these may be signs of a more serious allergic reaction (anaphylaxis).

• If your hives persist for more than a few days or recur frequently, as this may indicate chronic urticaria, which requires further evaluation and treatment.

• If you suspect a specific trigger, such as a medication or food, and need help identifying and avoiding it.

• If your symptoms do not improve with over-the-counter treatments or if you experience side effects from the medications.

• If you have other symptoms, such as fever, joint pain, or swelling, which may suggest an underlying condition.

• Urticaria or hives is a skin condition that occurs when the body's immune system reacts to an allergen or irritant and is characterised by itchy, raised welts or bumps that can appear anywhere on the body.

• Urticaria can be classified as acute, chronic, or physical, depending on the duration of symptoms, specific triggers, or underlying causes.

• If not managed timely, it can lead to several complications, some of which are severe, such as anaphylaxis, angioedema, and secondary infections.

• You can prevent urticaria by adopting several strategies like identifying and avoiding known triggers such as nuts, eggs, seafood, latex, pollen, and animal dander; managing stress levels; and maintaining good hygiene.