Anaphylaxis must be treated right away because it can cause death. Symptoms of anaphylaxis usually involve more than one part of the body such as the skin, mouth, eyes, lungs, heart, gut, and brain. Some symptoms include: 1  Skin rashes and itching and hives. 2  Swelling of the lips, tongue or throat. 3  Shortness of breath, trouble breathing, wheezing (whistling sound during breathing). 4  Dizziness and/or fainting. 5  Stomach pain, vomiting or diarrhea. 6  Feeling like something awful is about to happen.