Cypress IgE

If you live somewhere with cypress trees and your nose runs during cypress pollen season, this test answers a specific question: is cypress pollen one of the things your immune system is reacting to? It looks for a particular antibody (IgE) in your blood that targets cypress pollen proteins, which is the biological fingerprint of sensitization.

There is a second reason to care, and it surprises people. A subset of cypress-sensitized individuals also react to peach and other fruits, sometimes with severe whole-body reactions. This test, especially when paired with related allergen testing, can flag that hidden pattern before a serious reaction happens.

What This Test Actually Measures

This is a blood test for cypress-specific IgE (immunoglobulin E), an antibody your immune system produces after repeated exposure to cypress pollen. IgE is made by a type of white blood cell, and it sits on the surface of other immune cells waiting to recognize the allergen it was built for. When cypress pollen lands on those cells, the IgE binds it and triggers the release of histamine and other chemicals that cause sneezing, itching, watery eyes, and swelling.

This is a Tier 2 marker. Specific IgE assays are widely used clinically and are well validated for confirming sensitization, but the numeric level alone does not perfectly predict how severe your symptoms will be. The test tells you that your body recognizes cypress as a foreign trigger. Whether that recognition shows up as a runny nose, asthma, eye irritation, or nothing at all depends on the rest of your biology and your exposure.

Why Cypress Pollen Is Such a Big Deal in Some Regions

Cypress sensitization tracks tightly with where cypress trees grow. In a study of healthy adults in Tokyo, 46.8% had detectable cypress pollen-specific IgE in their blood, making it the second most common inhalant sensitization in that group after Japanese cedar. In France, IgE to a cypress allergen called Cup a 1 was about 7.4 times more common in high-pollen regions than in Paris. If you live in a cypress-heavy area, sensitization is not rare. If you do not, it is.

Timing also depends on geography. Mediterranean cypress (Cupressus sempervirens) typically pollinates in January and February, so symptoms can hit in winter, while Japanese cypress and other Cupressaceae species shift the peak into spring. The same antibody level means different things depending on what you breathe in every day and when.

Seasonal Allergic Rhinitis and Eye Symptoms

In a study of 89 cypress-allergic patients, the symptom pattern was striking. Every single person (100%) had rhinitis, meaning runny nose, congestion, sneezing. Between 74% and 89% had conjunctivitis (red, itchy, watery eyes), which is a higher rate than seen with many other pollen allergies. Asthma rates were comparatively low, between 7% and 19%.

Eye symptoms are a distinguishing feature of cypress allergy in a way that sets it apart from some other pollen allergies. If your main seasonal complaint is about your eyes, and you live somewhere with cypress, this test deserves a place in your workup.

The Pollen-Food Connection With Peach

Here is the part that catches people off guard. A cypress pollen protein called BP14 (also written as Cup s 7) belongs to a family known as gibberellin-regulated proteins. A related protein in peach (Pru p 7) shares enough structural similarity that your immune system can mistake one for the other. The result is a pollen-food allergy syndrome where cypress sensitization is linked to severe reactions when eating peach or other fruits.

In a Spanish study of 92 children with peach allergy, 16.3% had IgE against Pru p 7, and this sensitization was associated with severe reactions, upper airway symptoms, anaphylaxis (a whole-body allergic reaction that can be life threatening), and the presence of a cofactor like exercise that worsens the response. In an Italian study of 23 patients with suspected gibberellin-regulated protein allergy and 14 controls, 70% of the patients reacted to multiple foods, with peach the most common trigger. Basophil activation testing (a lab test using a person's blood to check whether allergy-driving white blood cells react to an allergen) was positive in about 87% of patients tested against the recombinant Pru p 7 protein, confirming the biology is real and clinically meaningful.

Reconciling the Surprising Pattern

This may feel contradictory. You can have a positive cypress IgE result with only mild seasonal sniffles, or you can have a positive result that signals a much more dangerous food allergy waiting to be triggered. Both are real, and they reflect which specific cypress protein your IgE recognizes. Not all positive results carry the same risk. Standard cypress IgE testing tells you that cypress is on your immune system's radar. Component testing for the specific protein Cup s 7, often ordered alongside Pru p 7, refines that signal into something more actionable. If your concern is severe fruit reactions, the cypress result is your starting point, not your endpoint.

How Cypress IgE Differs From Total IgE

A total IgE blood test measures all the IgE in your blood, regardless of what it targets. It can be high in people with many allergies, parasitic infections, or certain immune conditions. It can also be entirely normal in someone with a real, clinically obvious allergy. In the study of 89 cypress-allergic patients mentioned earlier, those who were allergic only to cypress had normal total IgE despite clear-cut symptoms. The cypress-specific test catches what total IgE misses, because it asks a precise question instead of a vague one.

When Results Can Be Misleading

A handful of factors can distort the interpretation of any specific IgE result, including this one. Knowing them up front helps you avoid acting on a misleading number.

• Anti-IgE biologic medications: if you are taking omalizumab, a drug used for severe asthma and chronic hives, your total IgE measurements will appear much higher than baseline because the drug forms long-lived complexes with IgE. In one study, total IgE rose from about 132 to 505 kU/L during treatment. The biologically active free IgE is actually lower, but standard assays cannot tell the difference.
• Inhaled or systemic corticosteroids: in a trial of 14 adults with atopic asthma, three months of inhaled beclomethasone at 800 micrograms per day reduced both total and specific IgE alongside symptom improvement. If you start or stop steroids around the time of testing, your numbers can shift.
• Recent allergen exposure: in one study, repeated nasal allergen exposure raised specific IgE by about 59% over eight weeks without changing total IgE. Testing during peak pollen season can produce a higher number than testing out of season for the same person.
• Cross-reactivity with related pollens: cypress IgE often shows up in people who are mostly sensitized to olive or plane tree pollen. In one German study, a large majority of those with cypress positivity were also sensitized to olive and plane. A positive cypress result does not always mean cypress is the dominant trigger.

Tracking Your Trend Over Time

A single cypress IgE result tells you whether you are sensitized right now. It does not tell you how that sensitization is changing. Specific IgE levels can rise during pollen season and after repeated exposure, and they can fall during long allergen avoidance or successful allergen immunotherapy. In a real-world study comparing severe asthma biologics, three months of benralizumab reduced total blood IgE by about 35%, while mepolizumab did not. These shifts matter for interpretation.

A reasonable cadence is to get a baseline test outside of peak pollen season, retest in 3 to 6 months if you start an intervention like allergen immunotherapy or a biologic, and then check at least annually if your symptoms or treatments change. Sampling when you are not in the middle of an asthma flare or actively reacting gives the most reliable comparison.

What an Unexpected Result Should Prompt

If your cypress IgE is positive and your symptoms match the local pollen calendar (rhinoconjunctivitis during cypress pollen season in a cypress region), the next step is usually confirming the timing of regional pollen release and discussing treatment options ranging from antihistamines and intranasal steroids to allergen immunotherapy. A randomized trial of 1,042 patients showed that the same dose of Japanese cedar pollen sublingual immunotherapy tablets was effective for allergic rhinitis caused by either cedar or cypress pollen. The picture is more nuanced than that single trial implies: other studies have found that only about half of cypress pollinosis patients clinically improve with cedar-only sublingual immunotherapy, and cypress-specific immunological responses are not always induced, so some experts argue that immunotherapy targeting both cedar and cypress may be needed for full benefit.

If your cypress IgE is positive and you have ever had a worrying reaction to peach or other fruits, especially with exercise as a trigger, the next step is component testing for Cup s 7 and Pru p 7, and a conversation with an allergist about the gibberellin-regulated protein syndrome. This is the pattern where a routine pollen result quietly flags a potentially severe food allergy. If your cypress IgE is positive but you have no symptoms and no clear exposure, the result alone does not require action. Sensitization is not the same as allergy, and many sensitized people never develop disease.

Putting It Together

Cypress IgE testing is most useful for two groups of people. The first is anyone with seasonal nasal or eye symptoms in a region where cypress is part of the pollen mix, where this test pins down a specific culprit. The second is anyone with a history of severe or unexplained food reactions, especially to peach, where cypress IgE can be the first hint of a less common but more serious cross-reactive syndrome. In both cases, the test result is the beginning of a workup, not the end of one.