For people bothered by tree pollen, March and April are usually the worst months, while those who are sensitive to grass pollen have problems in May and June. Ragweed and other summer weeds cause symptoms in late August and fall. But people who are allergic to house dust, molds, or animal dander can have symptoms year-round, since they are often constantly exposed to these allergens. Microscopic creatures called dust mites that live in carpets, bedding, and mattresses are thought to cause most house dust allergies. The most common food-borne allergens are specific proteins found in cow's milk, eggs, nuts, eggs, soybeans, fish, and shellfish.
Food allergies can cause cramping, bloating, vomiting, and diarrhea.
They also can cause a severe, life-threatening reaction called anaphylaxis, which may cause swelling of the lips, tongue, and throat. Anaphylaxis can be fatal unless treated. Always consult your own doctor about any opinions or recommendations with respect to your symptoms or medical condition. Beth Israel Deaconess Medical Center .