What to know about Shellfish Allergies
By Nicole Galan

The main symptoms of a shellfish allergy vary, but they can include vomiting, diarrhea, stomach pain, shortness of breath, coughing, chest pain, and swelling of the face, lips, tongue, or throat.
These symptoms can occur within minutes of ingesting shellfish, but they may sometimes not appear for several hours.
There are two different types of shellfish:
Crustaceans: Shrimp, crab, lobster
Mollusks: Clams, mussels, oysters, scallops, squid, octopus
Some people are allergic to one type of shellfish, while others are allergic to both. Most people with a shellfish allergy seem to be allergic to crustaceans, and the reactions to these foods tend to be more severe.
The doctor may recommend that people with any type of shellfish allergy avoid all shellfish due to the risk of cross-contamination or the development of new allergies.
Symptoms
The symptoms of a shellfish allergy may include:
vomiting
stomach pain
wheezing
shortness of breath
coughing
a tight throat or a hoarse voice
pale or blue discoloration of the skin
an itchy rash, or hives
swelling in the mouth or throat
dizziness
confusion
loss of consciousness
The symptoms of a shellfish allergy can vary among individuals and from one reaction to another. Sometimes, a reaction can be very mild and short, and other times, it can be more severe and last longer.
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