The response to a sting or bite from insects is variable and depends on a variety of factors. Most bites and stings result in pain, swelling, redness, and itching to the affected area. The skin may be broken and become infected if the bite area is scratched. If not treated properly, these local infections may become severe and cause a condition known as cellulitis. You may experience a severe reaction beyond the immediate area of the sting if you are allergic to the bite or sting. This is known as anaphylaxis. Symptoms of a severe reaction include hives, wheezing, shortness of breath, unconsciousness, and even death within 30 minutes. A sting on the tongue may cause throat swelling and death because of airway obstruction. Stings from large hornets or multiple (hundreds or thousands) bee stings have been rarely reported to cause muscle breakdown and kidney failure. Bites from a fire ant typically produce a pustule, or a pimple-like sore, that is extremely itchy and painful.

 

If you start to experience symptoms that are not just at the site of the bite or sting (and you don't have a history of severe reactions), seek medical attention. These symptoms (systemic symptoms affect the whole body) may progress to fatal anaphylactic shock. Hives are the most common systemic symptom. They appear as irregular, raised, red blotchy areas on the skin and are very itchy.  If the bite appears infected (redness with or without pus, warmth, fever, or a red streak that spreads toward the body), see a doctor.

 

Bruises develop when small blood vessels under the skin tear or rupture, most often from a bump or fall. Blood leaks into tissues under the skin and causes the black-and-blue color. As bruises heal, usually within 2 to 4 weeks, they often turn colors, including purplish black, reddish blue, or yellowish green. Sometimes the area of the bruise spreads down the body in the direction of gravity. A bruise on a leg usually will take longer to heal than a bruise on the face or arms.

Most bruises are not a cause for concern and will go away on their own. Home treatment may speed healing and relieve the swelling and soreness that often accompany bruises that are caused by injury. But severe bruising, swelling, and pain that begin within 30 minutes of an injury may mean a more serious problem, such as a severe sprain or fracture.

 

If you bruise easily, you may not even remember what caused a bruise. Bruising easily does not mean you have a serious health problem, especially if bruising is minimal or only shows up once in a while. Older adults often bruise easily from minor injuries, especially injuries to the forearms, hands, legs, and feet. As a person ages, the skin becomes less flexible and thinner because there is less fat under the skin. The cushioning effect of the skin decreases as the fat under the skin decreases. These changes, along with skin damage from exposure to the sun, cause blood vessels to break easily. When blood vessels break, bruising occurs.