Anaphylaxis
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
Anaphylaxis is a serious allergic reaction. It can begin very quickly, and symptoms may be life-threatening. The most common causes are reactions to foods (especially peanuts), medications, and stinging insects. Other causes include exercise and exposure to latex. Sometimes no cause can be found.
It can affect many organs:
- Skin - itching, hives, redness, swelling
- Nose - sneezing, stuffy nose, runny nose
- Mouth - itching, swelling of the lips or tongue
- Throat - itching, tightness, trouble swallowing, swelling of the back of the throat
- Chest - shortness of breath, coughing, wheezing, chest pain or tightness
- Heart - weak pulse, passing out, shock
- Gastrointestinal tract - vomiting, diarrhea, cramps
- Nervous system - dizziness or fainting
If someone is having a serious allergic reaction, call 911. If an auto-injector is available, give the person the injection right away.
Questions for your care team
General prompts to help prepare for your appointment.
- How does this information apply to my situation?
- Which symptoms or results need evaluation?
- Which tests are useful, and what can they tell us?
- What care options, benefits, and risks should we discuss?
- When should I seek urgent help, and whom should I call?
- When is follow-up, and how will we know whether the plan is working?
For a life-threatening emergency, call 911 in the U.S. or your local emergency number.
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