Fish Allergy

"The biggest drawback associated with fish allergy is cooking fumes. Many people suffer from asthma attacks or severe hives when someone cooks fish in the house. This affects the quality of life of the patients in a very important way".


How do I know if I have a fish allergy?

Fish allergy is the third cause of allergy after milk and eggs. A wide variety of fish can cause this allergy. Fish can be found in many foods and other products (e.g. medicines, beverages, gelatine, fishmeal, etc.). 

The major drawback associated with fish allergy is cooking vapors. Many people suffer from asthma attacks or severe hives when someone cooks fish in the house. That is to say, it is not simply a matter of avoiding consuming the food, but rather just remaining in a place where fish is cooked can cause serious reactions in these people, which makes the quality of life of these patients and their environment very affected.

In the Department of Allergology of the Clinic we have extensive experience in the treatment of food desensitization. Each patient is assessed individually and throughout the process is supervised by our team of allergists and nurses specialized in the control of this treatment.

What are the symptoms of fish allergy?

The first clinical manifestation of fish allergy can appear at any age but it is true that it is more frequent in the first two years of life, usually coinciding with the introduction of fish into the child's diet.

The symptoms of fish allergy are similar to other food allergies. They usually appear immediately after ingestion, contact or inhalation of the vapours from the cooking of the fish.

The symptoms begin with itching in the mouth and pharynx area, skin rashes with intense itching (hives) and in the most severe cases, angioedema. Respiratory symptoms such as rhinitis, conjunctivitis and asthma attacks are also frequent.

The most common symptoms are:

  • Itchy mouth and palate
  • Hives and beans by the skin
  • Rhinitis and/or conjunctivitis
  • Breathing difficulty
  • Asthma crisis
  • Vomiting, abdominal pain, nausea, vomiting and diarrhea may occur later

In the most severe cases, anaphylactic shock can develop, compromising the patient's life.

Do you have any of these symptoms?

You may have an allergy to fish and it may be possible to perform food desensitization treatment

What are the causes of fish allergy?

Many factors can cause the abnormal immune response to fish.

Previous contact with the fish, through the mother during pregnancy or breastfeeding or exposure to vapors during cooking and of course, ingestion triggers the excessive production of Ig E, causing the symptoms.

In Spain, fish such as hake, rooster, sardine, cod or whiting are the most common reactions.

The main fish allergen is a protein called parvalbumin found in fish muscle cells. They are thermostable proteins, this means that they are resistant to heat and they are not destroyed when cooking the fish.

Fish allergy is an allergy independent of seafood allergy and the simultaneous presence of both allergies is not very common.

Can fish allergy be cured?

In young children, allergy to fish may disappear but in general, it is frequent to persist and usually lasts longer than allergy to milk or eggs.

When fish allergy begins in adulthood, it is much more difficult to clear up and can last a lifetime.

If the treatment of food desensitization or induction of oral tolerance to fish is effective, these patients can eat the fish that caused their allergy again, including other types of fish, and can easily inhale the cooking steam. This improves their quality of life significantly.

How is fish allergy diagnosed?

<p>&nbsp;Pruebas cutaneas</p>

The diagnosis is made by means of a very simple skin test (prick test): drops containing a known amount of the allergen causing the allergy to the fish to which you may be sensitive are applied to the skin of the arm. The basis of this technique is to reproduce in the skin the reaction that we present in other parts of the body.

In addition, it is possible to perform blood tests, so that in a more precise way we can quantify and demonstrate the presence of specific Ig E against these proteins.

Sometimes, it is necessary to carry out a provocation test, which consists of observing under medical control the reaction that takes place after the ingestion of the food.

In addition to the usual skin tests, we can measure IgE by microarray, which gives us valuable information about the allergens that the patient recognizes.

How is fish allergy treated?

We have great experience in desensitizing to different foods such as eggs, milk and now also fish.

The first and most effective measure is to avoid contact with the allergen.

As in the case of fish allergy, even inhaling the steam from cooking the fish can trigger the symptoms, this makes avoidance with this food very difficult.

The desensitization treatment consists of initially administering very low doses and gradually increasing the dose, progressively and very slowly, until a complete portion of fish is tolerated.

This treatment requires that at all times, health personnel closely control this process to avoid significant allergic reactions.

This is complemented by education of the patient and his or her family to teach them to avoid contact with this food and to learn how to act in the event of a serious allergic reaction.

Learn about the fish desensitization treatment (avaliable in spanish)

Where do we treat it?


Department of Allergology
of the Clínica Universidad de Navarra

The Department of Allergy and Immunology of the Clinic is part of the Global Allergy and Asthma European Network, composed of the 25 best departments of Allergy in Europe, chosen for their scientific excellence, multidisciplinary work, teaching and international activities.

We have the most advanced diagnostic techniques, we are at the forefront of research and we collaborate with the best experts. We have more than 50 years of experience in the field.

What diseases do we treat?

Imagen de la fachada de consultas de la sede en Pamplona de la Clínica Universidad de Navarra

Why at the Clinica?

  • More than 50 years of experience.
  • Pioneers in the technique of molecular diagnosis by microarray.
  • Nursing specialized in allergic diseases and their care.