This is a way of treating allergies with a series of regular allergy shots. The shots actually contain a little bit of what the person is allergic to. By getting a tiny bit of the allergen, over a number of years, the body can learn to handle it better. Then, the person won't react so dramatically, with sneezing and wheezing, when the person does come in contact with the allergen. Immunotherapy can be especially helpful for people whose asthma symptoms are caused by allergies.