A firm, elevated swelling of the skin. Also called a weal or welt.
An inflammatory response to mild skin irritation, with a well-defined, raised redness, lasting for perhaps and hour and then disappearing. The cause is usually atopic allergies in an IgE-excess person, although mild, subclinical adrenocortical deficiency can be another factor.
Generally round, transient elevation of the skin, which is white in the center, with pale red edges; often accompanied by itching.
A smooth, round, elevated area of the skin with red edges and a white center, usually accompanied by itching; hives.
A swelling on the skin produced by a sting, an injection, an external force, or an internal reaction.
Individual lesion, usually with a red margin and pale center, of an itchy skin emption, characteristic of many allergic reactions.
A temporary red or pale raised area of the skin, often accompanied by severe itching. Wheals may be caused by scratching or rubbing the skin and are sometimes the sign of a local or general allergy.
A more or less round and temporary elevation of the skin, white in the center with a pale-red periphery, accompanied by itching. It is seen in urticaria, insect bites, anaphylaxis, and angioneurotic edema.
An elongated mark or ridge. Such a ridge is produced by intradermal injection.
Itchy, swollen lesion that lasts only a few hours; caused by a blow or scratch, the bite of an insect, urticaria (skin allergy), or the sting of a nettle. Examples include hives and mosquito bites.
A skin blister caused by hives, the lash of a whip, or an insect sting.