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Allergic reaction: when is it an emergency?
Mild allergic reactions cause itchy hives. A severe reaction, called anaphylaxis, can be life-threatening within minutes.
🔴 Go to the ER or call 911 if there is
- Trouble breathing, wheezing, or throat tightness
- Swelling of the lips, tongue, or throat
- Fainting, dizziness, or a weak pulse
- Vomiting after a known allergen
- Use an epinephrine auto-injector if prescribed, then call 911
🟠 Get care today if there is
- Hives spreading across the body
- A reaction to a new medicine
🟢 What helps at home
- An over-the-counter antihistamine as the label directs
- Avoid the trigger
Learn more from MedlinePlus, the U.S. National Library of Medicine: Allergic reaction →. This guide is general information for adults and caregivers. It is not medical advice, it cannot cover every case, and it is not a substitute for a clinician who can examine the person. When in doubt, seek care. FreeDoc is not affiliated with or endorsed by the National Library of Medicine.