Food allergies, infections, plants, medicines and insect bites can lead to an allergic reaction and hives, in which there is the formation of itchy skin welts, notes the American College of Allergy, Asthma & Immunology. Hives or urticaria also can develop on any area of the body, and the raised "wheals" or welts can be either small or large in diameter.
There are many urticaria triggers, as well as different types of urticaria, including physical, chronic and acute urticaria. Acute urticaria is a condition that may be present for nearly 6 weeks, according to WebMD. This urticaria type can develop due to an allergy to certain foods, such as nuts. Some other triggers of acute urticaria are latex and medications, such as aspirin. Triggers that can cause physical urticaria are exposure to heat, sun or cold stimuli that result in the formation of skin welts. Chronic urticaria can last longer than 6 months and may be linked to a cause such as an immunity issue.
A bacterial infection, such as strep throat, can also cause hives and its symptoms, states the American College of Allergy, Asthma & Immunology. When hives persists for a month or longer, patients should see a doctor for testing and diagnosis. Treatment options can include avoiding the specific trigger or taking prescribed antihistamines and antibiotics. In cases where hives and anaphylaxis are the symptoms of an allergic reaction, prompt medical attention is required.