An insect bite or sting will usually cause a swollen red area to develop on the skin. Most will settle on their own accord within a few hours or days. The severity of bites and stings will differ depending on the type of insect causing it and the sensitivity of the person.
Sometimes the insect bite can become infected with bacteria. An infection may occur if you scratch an insect bite, or it may be introduced into the skin at the time you are bitten. You may develop symptoms of a wound infection, such as pus or increasing pain, swelling or redness. Infections are usually treated with antibiotics.
Examples of insects that may bite or sting include wasps, hornets, bees, horseflies, ticks, mosquitoes, fleas, spiders, midges and bedbugs.
Some people may develop a mild allergic reaction to the bite or sting. this will usually cause a larger area or redness to develop.
Occasionally a more severe allergic reaction (anaphylaxis) can occur. This may cause swelling of the face, lips or tongue, dizziness, difficulty in breathing or fainting. This is a medical emergency and requires immediate medical attention. Call 999 if you suspect a medical emergency.