Some allergic reactions can be deadly. An anaphylactic reaction happens when a very large amount of histamine is released into your system at once causing a massive inflammatory reaction. Symptoms include difficulty breathing, wheezing, stomach pain and cramps, diarrhea, anxiety, swelling of the feet, hands, lips, eyes, and possible loss of consciousness. Death often occurs when airways swell shut. Portable epinephrine injectors, (one common brand is called the EpiPen) are designed to auto inject a hormone called epinephrine, which works rapidly and stimulates the heart, raises blood pressure and reduces swelling in the throat, lips, and face. In Canada, EpiPens are available with or without a prescription. Ask your healthcare provider for advice on whether you should have one available.