Mustard Allergy: Symptoms, Diagnosis and Treatment

Mustard Allergy: Symptoms, Diagnosis and Treatment


While it is often not recognized as such, mustard is a common food allergen. A food allergy occurs when a person’s immune system reacts in an abnormal way to a food that others normally tolerate. The allergy sufferer’s immune system views a protein in mustard as a foreign attacker, and releases histamine to combat the assault.

Symptoms of a Mustard Allergy

It is this release of histamine, not the allergen itself, that causes the symptoms experienced by those with a mustard allergy. These symptoms range from mild discomfort to the most extreme allergic reaction, anaphylaxis (anaphylactic shock). Depending on the severity of the reaction, allergy sufferers exposed to mustard can experience:

  • burning, tingling, or numbness in and around the mouth and the nasal cavity
  • swelling
  • itchy skin or hives
  • constriction of airways
  • weakness
  • dizziness
  • drop in blood pressure
  • rapid pulse
  • unconsciousness
  • death

How a Food Allergy is Diagnosed

It is important to determine whether or not a patient is experiencing a true food allergy, or a food intolerance. Treatments that target an immune response will not be effective for a food intolerance. There are two tests that can be used to diagnose a food allergy. Both measure the active protein in food allergic reactions, IgE.

The first, a skin prick test, involves injecting the suspected allergen just under the skin. If a bump forms, the allergy is confirmed. The second test involves sending blood to a laboratory to determine whether the patient has IgE antibodies for the food. Both methods are reliable, but the prick test provides a quicker result. In some cases, further tests may be necessary.

Avoiding Mustard in Prepared Foods

The primary treatment for any food allergy is avoiding the offending food. With mustard, this can be difficult, as it is not limited to the yellow spread used for sandwiches. Mustard seed, flour, and oil may be used in salad dressings, sauces, processed meats, and many other prepared foods.

While mustard-derived ingredients may be specifically listed on food labels, it may also be hidden in a list of ingredients as “natural flavors” or “spices.” Because of this, allergy sufferers may need to consult food manufacturers to determine if mustard is an ingredient before using a product.

Nearly all restaurants use mustard spread. Cross-contamination can occur, even when customers specifically order items without mustard. Additionally, restaurant employees often do not know the full list of ingredients for condiments and menu items. Allergy sufferers must question restaurant employees and use their own judgment when ordering. Diners might bring small containers of dressings or condiments from home to avoid unknown concoctions in restaurants.

Effects of Repeated Exposure to a Food Allergen

An allergic reaction to a food requires a previous exposure and sensitization to the food. For this reason, a person with an allergy can consume an allergen for years before showing the first symptom of a food allergy.

Likewise, repeated exposures to the allergen can intensify subsequent reactions. An allergy sufferer may have numerous mild reactions to the allergen, and suddenly have a life-threatening immune response. Because of this, it is unwise for anyone to knowingly consume an allergen, even if his or her past reactions have always been mild.

Treatment Options

At this time, there is no standard preventative or maintenance treatment for a mustard allergy. Allergy shots, a form of immunotherapy, are not currently used for food allergies. Minor allergic reactions can be allowed to run their own course, or reversed with an antihistamine such as Benadryl®.

Stronger reactions can be treated with a shot of epinephrine, also called adrenaline. All food allergy sufferers should consult their doctor to determine if they should carry a self-administered shot of this drug for emergencies. This is available under brand names such as EpiPen® and Twinject®.