What should you know about hives spreading all over the body?

Urticaria produces raised, changing welts that can join together and cover large areas. Each welt may fade while another appears, so the pattern can seem to travel across the trunk, limbs, or face. Common associations include a recent infection, medicine, food, heat, cold, pressure, or exercise, but the appearance alone cannot identify the trigger. Swelling deeper under the skin, called angioedema, may affect the lips, eyelids, hands, or feet.

Check how you feel overall, not only how much skin is involved. Photograph the rash, write down when it began, and list new medicines, foods, illness, products, and activities. Cool compresses and loose clothing may reduce discomfort; avoid hot showers and rubbing the welts. Ask a pharmacist or clinician about an oral antihistamine that fits your age, pregnancy status, and existing medicines. If the outbreak is new, extensive, or recurring, arrange assessment so the pattern and possible cause can be reviewed.

Call emergency services for hives with swelling in the tongue, mouth, or throat; difficulty breathing or swallowing; wheezing; sudden weakness; faintness; or repeated vomiting. A severe reaction can worsen quickly. Obtain prompt medical advice if the rash is accompanied by fever, marked pain, bruising, blisters, or lesions that do not move or fade. Do not wait for the skin area to become larger before acting on breathing or airway symptoms.

Could this be urticaria with angioedema? Which recent exposure deserves attention? What medicine is suitable for me? Which symptoms mean I should seek emergency help?