Shellfish allergy symptoms generally develop within minutes to an hour of eating shellfish. They may include:

  • Hives, itching or eczema (atopic dermatitis)
  • Swelling of the lips, face, tongue and throat, or other parts of the body
  • Wheezing, nasal congestion or trouble breathing
  • Abdominal pain, diarrhea, nausea or vomiting
  • Dizziness, lightheadedness or fainting
  • Tingling in the mouth

Allergies can cause a severe, potentially life-threatening reaction known as anaphylaxis. An anaphylactic reaction to shellfish or anything else is a medical emergency that requires treatment with an epinephrine (adrenaline) injection and a trip to the emergency room.

Signs and symptoms of anaphylaxis include:

  • A swollen throat or a lump in your throat (airway constriction) that makes it difficult for you to breathe
  • Shock, with a severe drop in your blood pressure
  • Rapid pulse
  • Dizziness, lightheadedness or loss of consciousness

When to see a doctor

See a doctor or allergy specialist if you have food allergy symptoms shortly after eating. Seek emergency treatment if you develop signs or symptoms of anaphylaxis.

Jul. 12, 2014

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