Definition | Causes | Risk Factors | Symptoms | Diagnosis | Treatment | Prevention

Causes

Substances that cause anaphylaxis are often called allergens or triggers. Common triggers include:

Allergic Reaction to Medication (Hives)

Hives Medication
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Some triggers, like dyes used in x-ray procedures, can cause a reaction similar to anaphylaxis.

Symptoms

The symptoms of anaphylaxis usually occur within minutes after exposure to an allergen, but can occur hours later. Symptoms may be mild or very severe, including death. They include:

  • Hives and itching
  • Warmth or redness of skin
  • Swelling, redness, stinging or burning, especially on the face, mouth, eyes, or hands
  • Lightheadedness, pale/blue skin color, low pulse, dizziness
  • Obstruction of the nose, mouth, and throat
  • Severe respiratory distress (eg, chest tightness, shortness of breath, wheezing)
  • Nausea, vomiting, cramping, diarrhea, or abdominal pain
  • Heart arrhythmias
  • Convulsions
  • Low blood pressure
  • Shock
  • Feelings of anxiety

Treatment

Anaphylaxis is a medical emergency that requires immediate medical treatment, including:

NOTE: If you receive emergency epinephrine, you should go to the emergency room right away, even if your symptoms have gone away.

If you are diagnosed with anaphylaxis, follow your doctor's instructions .