Yellow Hornet I5 IgE (I5) — what this allergy blood test means Biomarker Testing
It measures IgE antibodies to yellow hornet venom to assess allergy risk and guide follow-up testing, with easy ordering and results via Vitals Vault/Quest.
With Vitals Vault, you have access to a comprehensive range of biomarker tests.
A Yellow Hornet I5 IgE test is a blood test that looks for allergy antibodies (IgE) directed against yellow hornet venom. It is most useful when you have had a sting reaction and you and your clinician are trying to understand whether venom allergy is likely.
This test does not “prove” how severe your next sting will be, but it can help connect a real-world reaction to an immune signal that supports next steps. Those next steps may include additional venom testing, a referral to an allergist, and discussion of emergency preparedness.
Because venom allergies can overlap across related insects, your result is usually interpreted alongside your history and often alongside other venom-specific IgE tests. That context is what turns a number on a report into a practical plan.
Do I need a Yellow Hornet I5 IgE test?
You may want this test if you were stung and developed symptoms beyond a small, local reaction. Concerning reactions can include widespread hives, swelling away from the sting site, throat tightness, wheezing, dizziness, fainting, or vomiting soon after the sting.
This test can also be helpful if you have a history of anaphylaxis (a severe allergic reaction) after a sting but you are not sure which insect was responsible. Yellow hornets are part of the stinging insect (Hymenoptera) group, and people often misidentify the insect, so lab testing can help narrow the picture.
You might not need venom-specific IgE testing if your only symptoms were localized redness, warmth, and swelling that peaked over 24–48 hours and then improved. Large local reactions can be uncomfortable, but they do not automatically mean you have a systemic venom allergy.
Testing supports clinician-directed care and follow-up planning. Your symptoms, timing, and any treatment you received (such as epinephrine) matter as much as the lab value.
This is typically a CLIA-laboratory immunoassay for allergen-specific IgE; results should be interpreted with your clinical history and are not a standalone diagnosis of venom anaphylaxis risk.
Lab testing
Order Yellow Hornet I5 IgE through Vitals Vault when you’re ready to confirm sensitization and plan next steps.
Schedule online, results typically within about a week
Clear reporting and optional clinician context
HSA/FSA eligible where applicable
Get this test with Vitals Vault
Vitals Vault lets you order Yellow Hornet I5 IgE testing without needing to coordinate the logistics yourself. You complete checkout, visit a participating lab location for a standard blood draw, and then review your results when they are ready.
If you are trying to make sense of a sting reaction, PocketMD can help you turn your report into a structured set of questions for your clinician. That can include whether you should add other venom IgE tests, whether skin testing is appropriate, and how to think about emergency preparedness.
If your result is borderline or your sting reaction was recent, you may also want a plan for retesting. Vitals Vault makes it easy to reorder the same marker or broaden to a more complete venom allergy workup when your clinician recommends it.
- Order online and complete a standard blood draw at a participating lab
- Clear, shareable results you can bring to your clinician or allergist
- PocketMD support to help you interpret results and plan next steps
Key benefits of Yellow Hornet I5 IgE testing
- Helps confirm whether your immune system has made IgE antibodies to yellow hornet venom after a sting reaction.
- Supports risk stratification when your symptoms suggest a systemic reaction rather than a simple local sting response.
- Guides which additional venom tests to consider, since cross-reactivity between stinging insects is common.
- Provides objective data to support allergist referral and discussion of venom immunotherapy when appropriate.
- Helps clarify confusing histories when the insect was not clearly identified at the time of the sting.
- Can be used as part of follow-up when prior testing was negative but your reaction history remains concerning.
- Creates a baseline result you can track over time alongside symptoms and clinician recommendations.
What is Yellow Hornet I5 IgE?
Yellow Hornet I5 IgE is an allergen-specific IgE blood test. It measures whether your immune system has produced IgE antibodies that recognize proteins in yellow hornet venom.
IgE is the antibody class involved in immediate-type allergic reactions. If you are sensitized, IgE bound to mast cells and basophils can trigger release of histamine and other mediators when you are stung again. That is what can lead to hives, swelling, breathing symptoms, low blood pressure, or anaphylaxis in some people.
A positive result means sensitization is present, but it does not automatically predict reaction severity. Some people have detectable venom-specific IgE and never have a systemic reaction, while others have severe reactions with only modest IgE levels. That is why your clinician will weigh your test result together with what happened during your sting event.
This test is one piece of venom allergy evaluation. Depending on your case, an allergist may also use skin testing, measure baseline tryptase, or order a broader panel of venom-specific IgE tests to related insects.
What do my Yellow Hornet I5 IgE results mean?
Low (negative) Yellow Hornet I5 IgE
A low or negative result means the test did not detect measurable IgE to yellow hornet venom. If your sting reaction was mild and localized, that often fits well with the overall picture. If you had a clear systemic reaction, a negative result does not fully rule out venom allergy, especially if testing was done soon after the sting or if the culprit insect was different than suspected. Your clinician may recommend testing to other venoms, repeating testing after more time has passed, or proceeding to skin testing with an allergist.
In-range results (interpreted by the lab’s class or cutoff)
For allergen-specific IgE, labs usually report results as a concentration with a cutoff for “negative” versus “positive,” and sometimes a class level. An in-between or borderline result can happen when sensitization is low-level, when there is cross-reactivity with related venoms, or when timing and recent exposures affect the immune signal. In this situation, your sting history becomes the deciding factor for next steps. Many clinicians confirm with additional venom IgE tests or allergist-directed skin testing before making long-term decisions.
High (positive) Yellow Hornet I5 IgE
A high result indicates sensitization to yellow hornet venom, meaning your immune system has IgE that recognizes it. If you also had symptoms consistent with a systemic reaction, this combination strengthens the case for venom allergy evaluation and a prevention plan. Your clinician may discuss carrying epinephrine, avoiding high-risk exposures, and referral to an allergist to consider venom immunotherapy. If you did not have systemic symptoms, a positive result may represent sensitization without clinical allergy, so treatment decisions should still be based on your history.
Factors that influence Yellow Hornet I5 IgE
Timing matters: testing very soon after a sting can sometimes miss a developing IgE response, while testing later may be more informative. Cross-reactivity between stinging insects can also affect results, because some venom proteins are similar across species. Medications do not usually “hide” IgE in the way they can affect skin testing, but immune conditions and very young age can influence antibody patterns. Most importantly, insect identification is often uncertain, so your clinician may interpret this result alongside other venom IgE tests rather than in isolation.
What’s included
- Yellow Hornet (I5) Ige
Frequently Asked Questions
Do I need to fast for a Yellow Hornet I5 IgE blood test?
Fasting is not typically required for allergen-specific IgE testing. You can usually eat and drink normally unless your clinician paired this test with other labs that require fasting.
How soon after a sting should I get venom-specific IgE testing?
If you test too soon after a sting, IgE levels may not yet be detectable in some people. Many clinicians consider testing a few weeks after the reaction, and they may repeat testing if the history is strongly suggestive but results are negative or borderline. Your allergist can advise the best timing for your situation.
Does a positive Yellow Hornet I5 IgE mean I will have anaphylaxis next time?
No. A positive result shows sensitization, not certainty about reaction severity. Your risk assessment depends on your prior reaction (especially breathing symptoms, low blood pressure, or fainting), other test results, and your overall health.
What is the difference between venom IgE blood testing and skin testing?
Blood testing measures circulating allergen-specific IgE in your serum. Skin testing measures how your skin reacts to tiny amounts of venom under controlled conditions and can sometimes detect sensitization when blood tests are negative. Allergists often use both approaches, depending on history and prior results.
Should I test for other stinging insects too?
Often, yes. People may be sensitized to more than one venom, and cross-reactivity can make a single test hard to interpret. If your history suggests a systemic reaction, your clinician may add other venom-specific IgE tests (such as to yellow jacket, honey bee, or wasp) or refer you for a comprehensive venom evaluation.
Can I use this test to monitor venom immunotherapy (allergy shots)?
Venom immunotherapy decisions are usually guided by your clinical course and allergist protocols. Specific IgE levels can change over time, but the number alone is not a reliable measure of protection. If you are on immunotherapy, follow your allergist’s monitoring plan and use labs as supportive data.