Allergy is an abnormal response in our bodies to common substances, such as plants, foods, household dust and pets or medications. People with allergies may have symptoms such as sneezing, cough, itching and increase secretions (runny nose, tears, etc.) Risks for allergy include genetics (family history) and environment. Certain tests and treatment are possible for many forms of allergy. Sinusitis may also present with similar symptoms (congestion, nasal drainage).