Allergies are what happens when our immune system fights foreign bodies like pollen, foods, drugs, even materials like nickel or latex. Allergic reactions can range from minor to life-threatening. They may be annoying, like a stuffy nose caused by seasonal allergies, or potentially harmful, like anaphylaxis caused by a food allergy.
The same substances that cause allergies can also trigger asthma symptoms. Asthma is a chronic (life-long) disease that can cause wheezing, coughing, and shortness of breath. Like with allergies, asthma symptoms are the body's response to a foreign substance, but with asthma, the reaction affects a person's lungs and airways.