Hives have a few key features that may distinguish them from a number of other reactions. The most common identifying characteristics of Hives are:
- A well-defined area of swelling, round or flat in formation,
but always raised above the surrounding skin
- Varying in size from 1-inch to many inches in diameter
Hives tend to come and go in crops and commonly last for about 24 hours. You may monitor your Hives by circling a spot and then look at it a day later to take note of any changes in size or shape. An occurrence of Hives may clear in a day but can last for much longer. Although broken or scabbing skin is not a direct symptom of Hives, it can result from scratching the affected area. Heat can also cause your Hives to worsen and spread. In extreme cases, your airways can swell, causing wheezing and respiratory distress, or even hindering your ability to breathe at all.