An allergic reaction usually occurs within minutes of contact with an allergen, but can also occur several hours after exposure. A reaction can include any of the following symptoms, and a person may experience one or more of these symptoms, regardless of the allergen:
- Skin System: hives, swelling, itching, feeling hot, redness, rash
- Respiratory System (breathing): coughing, wheezing, shortness of breath, pain or tightness in the chest, tightness in the throat, hoarse voice, nasal congestion or "hay fever" type symptoms (runny or itchy nose, watery eyes, sneezing), difficulty swallowing
- Gastrointestinal System (stomach): nausea (upset stomach), pain or cramps, vomiting, diarrhea
- Cardiovascular System (heart): pale or bluish complexion, weak pulse, loss of consciousness, lightheadedness/dizziness, shock
- Other: anxiety, feeling of "impending doom", headache, uterine cramps, metallic taste in the mouth
The most dangerous symptoms of an allergic reaction are:
- Difficulty breathing caused by swelling of the airways (including a severe asthma attack in asthmatics);
- A drop in blood pressure causing dizziness, discomfort, a feeling of weakness or loss of consciousness.
- These two symptoms can lead to death if not treated.
Remember:
- Do not neglect the first symptoms.
- Always take a potential reaction seriously and act quickly.
- Reactions are not all alike; the symptoms a person experiences may vary from one episode to another.
- Anaphylaxis can occur even in the absence of skin symptoms such as hives.
- A child may describe their symptoms differently than an adult: for example, they might say "my throat feels ticklish" or "my tongue feels prickly."