What should I do if I have a large area of itchy skin due to allergies?

When experiencing extensive itching due to allergic skin reactions, the following measures can be taken to relieve symptoms: 1. Topical medications: If the allergic reaction has not caused blisters or skin erosion, calamine lotion or compound menthol cream can be applied to relieve itching. If skin breakdown or exudation has occurred, boric acid solution can be used for wet compresses, followed by the application of hydrocortisone butyrate cream or tacrolimus ointment to alleviate symptoms. 2. Oral medications: Oral antihistamines can help calm the skin and reduce itching and swelling. If there is a significant inflammatory response, glucocorticoid medications such as prednisone tablets or dexamethasone tablets may be considered. 3. Identify and avoid allergens: Visit a hospital for allergy testing as soon as possible to identify the allergen. Once the cause is determined, avoid contact with these allergens in daily life to prevent recurrence or worsening of allergic symptoms. 4. Dietary adjustments: Avoid consuming spicy, irritating foods and seafood. Drink plenty of water to accelerate metabolism and promote recovery. 5. Cold compress: Apply cold normal saline or an ice pack to the affected area to reduce local skin temperature, helping to alleviate swelling and itching.