Milk, fish and shellfish, nuts, wheat, and eggs are among the most common foods that cause allergies. A food allergic reaction usually occurs within minutes of eating the offending food, and symptoms can include asthma, hives, vomiting, diarrhea, and significant swelling in the area around the mouth. The best treatment is to avoid the offending food altogether; but when exposed, treatment with antihistamines or steroids is recommended. In life-threatening situations, an epinephrine injection is needed to reverse symptoms.
Some people develop allergies to certain drugs, such as penicillin or aspirin. Symptoms can range from mild to life-threatening and can include a skin rash or hives, itchy eyes, congestion, and swelling in the mouth and throat. The best treatment of drug allergies is to avoid the offending drug altogether; however, when exposed, treatment with antihistamines or steroids is recommended. For coughing and lung congestion, drugs called bronchodilators may be prescribed to widen the airways. For more serious symptoms epinephrine may be needed.