Treating an Allergy
In the majority of cases knowing the cause of the allergy will be enough to make life a lot easier, you'll just have to avoid eating those foods or eating any foods that contain the allergen, or you will have to avoid pollen and take antihistamines.
However in some cases you can take this one step further and make life even easier – by getting treated for the allergy using 'immunotherapy' treatment. Here you will have your system gradually introduced to tiny amounts of the allergen but these amounts will increase with each administering. This will then allow the allergen to sneak in under the system's radar. When it doesn't cause any harm your body will then begin to recognize that it is not harmful and the allergic reactions will cease. This won't work in all cases however and is only appropriate for some allergies.