Allergy & immunology · Cincinnati
Allergy shots and immunotherapy safety
Allergy shots treat the cause of allergies rather than only the symptoms. Dr. David I. Bernstein has directed the North American Immunotherapy Safety Surveillance Study since 2008, the largest ongoing study of how to give allergy shots safely.
What allergy shots do
Allergen immunotherapy gives gradually increasing doses of the things you are allergic to, such as pollen, dust mites, pet dander, mold or insect venom. Over time the immune system becomes less reactive, so symptoms and medicine use go down, and the benefit often lasts after treatment ends.
Treatment begins with a build-up phase, usually one or two injections a week, followed by maintenance injections every few weeks, typically for three to five years. For some allergies, tablets dissolved under the tongue at home are an alternative.
Who may benefit
- Allergic rhinitis (hay fever) not controlled by medicines
- Allergic asthma, once asthma is well controlled
- Allergic conjunctivitis (itchy, watery eyes)
- Severe reactions to bee, wasp or other insect stings
- People who want to reduce long-term medicine use
What the national safety data show
The ACAAI/AAAAI surveillance study, which Dr. Bernstein directs, has surveyed practicing allergists every year since 2008.
injection visits tracked from 2008 to 2023, covering 4.9 million patients.
of injection visits had a systemic reaction, most of them mild.
injection visits led to a fatal reaction (2008–2018), down from earlier estimates of about 1 in 2.4 million.
Sources: the surveillance study publications listed below. These figures describe large populations, not any individual’s risk.
What makes allergy shots safer
The surveillance study identified practices linked to fewer severe reactions. Dr. Bernstein’s published recommendations for allergists include:
Check asthma first
Screen for recent worsening of asthma before each injection, and do not give shots when asthma is severe and uncontrolled.
Prevent dosing errors
Use clinic protocols to confirm the right patient, vial and dose every time.
Adjust doses when needed
Lower doses after gaps in treatment and consider adjustments during peak pollen season for higher-risk patients.
Watch for 30 minutes
Observe every patient for at least 30 minutes, track the time and have patients check out with staff.
Common questions
Are allergy shots safe?
For most people, yes. In the North American surveillance study Dr. Bernstein directs, covering 84.1 million injection visits from 2008 to 2023, fatal reactions were extremely rare and injection-related infections were almost nonexistent. Mild local swelling at the injection site is common.
Why do I have to wait 30 minutes after a shot?
Nearly all serious reactions start within 30 minutes of an injection. Practices that tracked the waiting time and had patients check out with staff had significantly fewer severe reactions.
Can I get allergy shots if I have asthma?
Often, yes, but asthma must be well controlled. Uncontrolled or severe asthma is the most important risk factor for severe reactions, so your breathing is checked before each injection.
What if I miss shots?
Your dose may be lowered for a while after a gap. Surveillance data show that practices adjusting doses after long gaps had fewer severe reactions.
Are under-the-tongue tablets an alternative?
For grass, ragweed and house dust mite allergy, tablets taken at home are an option. Their safety profile is favorable, and no fatal reactions to them had been identified as of 2020.
How long does treatment last?
Shots start with a build-up phase of gradually increasing doses, then maintenance injections, typically for three to five years.
Dr. Bernstein’s research
Since 2008 Dr. Bernstein has led the North American Immunotherapy Safety Surveillance Study, sponsored by the American College of Allergy, Asthma and Immunology and the American Academy of Allergy, Asthma and Immunology. Its findings shape how allergists across the United States give allergy shots, including post-injection monitoring, asthma screening and dose adjustment after missed injections.
He has also been an investigator in clinical trials of sublingual immunotherapy tablets and a co-author of national practice parameters on allergen immunotherapy.
Selected publications
- Epstein TG, Berendts K, Bernstein DI. Impact of dose adjustment after gaps in subcutaneous immunotherapy: update from the North American Immunotherapy Surveillance Study (2008–2023). J Allergy Clin Immunol Pract. 2025. PubMed · DOI
- Epstein TG, Murphy-Berendts K, Liss GM, Bernstein DI. Risk factors for fatal and nonfatal reactions to immunotherapy (2008–2018): postinjection monitoring and severe asthma. Ann Allergy Asthma Immunol. 2021. PubMed · DOI
- Bernstein DI, Epstein TEG. Safety of allergen immunotherapy in North America from 2008–2017: lessons learned from the ACAAI/AAAAI National Surveillance Study. Allergy Asthma Proc. 2020. PubMed · DOI
- Bernstein DI, Epstein TG. Safety of subcutaneous allergen immunotherapy. Allergy Asthma Proc. 2022. PubMed · DOI
- Bernstein DI, et al. Managing risk of anaphylaxis in patients receiving allergen immunotherapy: assessing benefit versus risk. J Allergy Clin Immunol. 2022. PubMed · DOI
- Bernstein DI. Aeroallergen immunotherapy update: developments since the third practice parameter. Allergy Asthma Proc. 2025. PubMed · DOI
Considering allergy shots?
Request a consultation. Dr. Bernstein reviews every request personally.