The Sneeze

What is Pollen-Food Allergy Syndrome (PFAS)?

April 20, 2023

Written By:

Andy Dang, MD, FAAAAI

What is PFAS?

Have you ever felt throat, tongue, or mouth irritation after eating raw fruits, veggies, or nuts? If you answered "Yes,," then you may have a condition called Pollen-food Allergy Syndrome (PFAS), also known as "Oral Allergy Syndrome" (OAS). 


PFAS is one of the most common types of food allergy though many people with this type of food allergy do not realize they have the syndrome. Most people will avoid or dislike these foods due to the symptoms. Some people develop symptoms as children, end up disliking the foods, and become adults and continue to avoid and dislike the foods, but do not realize why.

How does PFAS occur? 

Symptoms of PFAS occur because of localized contact irritation caused by pollen-related proteins found in raw fruits, veggies, and nuts. Individuals who already have pollen allergies consume these foods, and immune cells misinterpret such proteins as pollen allergens instead, which leads to the immune cells to overreact and release inflammatory substances like histamine, which then leads to symptoms of itching, tingling, irritation, and/or slight swelling. Symptoms can vary depending on the fluctuations in the pollen season as well. All patients with PFAS have pollen allergies, but it is possible to have a patient with mild pollen allergies that he or she is unaware of. An evaluation by an allergist can help clarify this situation.

What are the Common Food Triggers of PFAS? 


Typical patterns of cross-reactivity between pollen, fruits, vegetables, and nuts are shown below. Individual foods are grouped by their taxonomic families.

Cross-reactivity patterns in oral allergy syndrome (pollen-food allergy syndrome) Adapted and extended from: Sicherer SH. Clinical implications of cross-reactive food allergens. J Allergy Clin Immunol 2001; 108:881. 


How to Treat Symptoms of PFAS

Usually symptoms affecting the mouth and throat are mild, resolve quickly, and do not need treatment. There are a few ways to potentially treat the symptoms:

• Pre-Medicating

Take an oral non-drowsy 24hr antihistamine (such as cetirizine, loratadine, fexofenadine, levocetirizine) prior to consuming trigger foods.  You can also take the antihistamine after consuming the food.

• Consume Fully Cooked Foods

Consume fully cooked forms of the foods as this will break/change the cross-reactive proteins and mitigate or eliminate symptoms.  The more a food is cooked, the less it resembles pollen.

• Avoid Foods That Aren’t Tolerable

Individuals can avoid consuming foods that trigger symptoms.

• Allergy Immunotherapy Shots

Allergen immunotherapy (allergy shots) to treat/cure pollen allergies can sometimes fix PFAS!  Allergy shots work by creating a mixture of pollen that is injected into the body repeatedly in gradually increasing amounts, which desensitizes the immune system and can potentially cure the pollen allergy and PFAS.

There is a small chance that more severe systemic symptoms may occur rarely which may require carrying an epinephrine autoinjector--please discuss with your Ohio food allergist to decide if you need a prescription.

Need PFAS Treatment? Contact Premier Allergy & Asthma Today!

If you want to learn more about PFAS, need help with diagnosing and treating PFAS, schedule an appointment to speak with an allergist at Premier Allergy & Asthma. Premier Allergy & Asthma has 11 locations in Ohio, and patients can schedule an appointment with their allergists to help diagnose and treat Pollen-Food Allergy Syndrome.

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