Cause of hives
Hives are a form of rash characterized by raised blisters filled with liquid. Hives have several underlying causes, all of which have in common the release of histamine, an inflammatory mediator of the body. This acts on small blood vessels in the skin by promoting blood circulation and making the vessels more permeable.
As a result, fluid leaks from the blood vessels into the surrounding skin and causes the fluid-filled blisters that are characteristic of hives. The general cause for the development of wheals is therefore an excessive immune reaction. This can be caused by allergies or by the so-called hives.
On the other hand, insect bites can be the cause, where the immune reaction against the insect venom and the increased scratching at the bite site leads to the formation of hives. With very sensitive skin, mechanical overloading of the skin alone, for example by rubbing clothing, heat or cold, can lead to the formation of wheals. Certain infectious diseases, such as measles, also lead to the formation of wheals.
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