Seafood and Shellfish Allergies by Daniel Jo

Daniel_outsideAmericans love seafood. Shrimp, lobster, clams: it’s hard to imagine that people have to avoid it. A seafood allergy is a common food allergy that roughly effects 7 million Americans, accordingly to a nationwide survey. Did you know that along with fish, shellfish allergies are the most common adult-onset food allergy? Those afflicted with serious seafood allergies must use extreme caution. An allergic reaction to shellfish can cause life-threatening anaphylaxis which is a sudden, severe, potentially fatal reaction that results in low blood pressure and throat swelling, making it difficult to breathe.

There are two known proteins that cause seafood allergies, parvalbumins in fish and tropomyosins in shellfish.  Symptoms of a shellfish allergy can take some time to set in, but most develop within minutes. Some symptoms include: itching, hives, swelling of the face, lips, tongue, tingling in the mouth and trouble breathing. Shellfish allergies differ from other food allergies because they’re unpredictable and can become more severe with each exposure.

There are often misconceptions about iodine allergies. Some believe that if you have seafood allergies, you are also allergic to iodine. Recent studies have found there is no relationship between iodine and seafood allergies. It is safe for those who have seafood allergies to have a CT scan or any other iodinated contrast media radiographic test done.

Though there is no known cure for a seafood allergy, here are some quick tips on how to avoid a reaction:

  1. Avoid foods such as shrimp, lobster, crab and other crustaceans
  2. Be aware that cross-contamination can happen, so you may want to avoid seafood altogether
  3. Doctors will most likely recommend you carry an epinephrine pen (EpiPen, Auvi-Q) for self-administration in case you accidentally ingest any. Epinephrine (adrenaline) is the first-line treatment for anaphylactic shock
  4. Read food labels. Companies are now required to disclose whether their food product contains shellfish. However, they aren’t required to disclose if the product has mollusks (oysters, scallops). Proceed with caution!
  5. Let people know you have an allergy. It’s more common nowadays that restaurants cater to ‘people suffering from allergies.’ If you’re out to dinner or simply at a grocery store, tell the waiter you have a seafood allergy and ask a customer service rep at the store to help locate some seafood-free foods


Seafood allergies are not to be taken lightly; it’s best to use caution than risk having a fatal reaction.  Remember, an allergy to shellfish may develop any time during a person’s life and it can be caused by foods that you’ve eaten before. Listen to your body and know when to see a doctor.

The information provided is for general interest only and should not be misconstrued as a diagnosis, prognosis or treatment recommendation. This information does not in any way constitute the practice of medicine, or any other health care profession. Readers are directed to consult their health care provider regarding their specific health situation. Marque Medical is not liable for any action taken by a reader based upon this information.



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