An allergy is your body’s hypersensitive reaction to a normally harmless substance. These substances, be they food, pollen, a bee sting, dust mites, or a host of others, are called allergens. In the body of an allergic person, the immune system reacts abnormally when an allergen is brought into contact or absorbed by their body. As the allergy season progresses, many people complain of fatigue, exhaustion and lethargy. Allergies are one of the most common ...