A skin rash from an insect bite is an allergic reaction that affects the skin, according to MayoClinic.com. It is not uncommon for an insect bite to cause hives, but the severity of the rash can vary from person to person. An insect bite allergy occurs in a person who has a hypersensitivity to the venom of a particular insect, such as wasps or fire ants, according to Penn State University. A skin rash from an insect bite should be evaluated by a medical doctor.
Hives are an allergic reaction that surfaces on the skin with inflammation, itchiness and redness, according to Penn State University. When the venom enters the bloodstream of the person, the immune system attempts to fight it off by unleashing antibodies, which in turn release histamine. Histamine causes the skin to become inflamed and itchy.
Itching and swelling on the surface of the skin are the two most common symptoms of a skin rash from an insect bite, according to Medline Plus. As the skin reacts, it develops welts that appear to move, spread, get bigger and join together in a matter of seconds or minutes. The hives can change shape, appear and disappear in a short amount of time. The more someone scratches the welts, the more the hives will spread.
The best treatment is to avoid exposure to potentially harmful insects. As soon as the person is bit by an insect, remove the stinger, apply a cold ice pack and apply a topical hydrocortisone cream, according to Penn State University. MayoClinic.com recommends taking an oral antihistamine containing diphenhydramine as soon as possible to reduce the amount of histamine the body is able to create.
A skin rash from an insect bite may be the first symptom of a severe allergic reaction. If the hives affect the throat or ears, the person may experience swelling, obstructing the ability to breathe, according to Medline Plus. If hives are accompanied with swollen lips or throat, dizziness, confusion, nausea, vomiting, lightheadedness or difficulty breathing, call 911 for immediate medical attention, according to MayoClinic.com. Another common complication is developing secondary infections in the skin due to open cuts and wounds caused by scratching.
Someone who is allergic to insect bites should wear a medical I.D. bracelet to identify her condition. In the rare case that the person has a severe allergic reaction, emergency responders will know the person's condition and how to effectively treat her.