What is the recommended time interval between receiving an allergy shot and a flu (influenza) shot?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: November 28, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Timing Between Allergy Shots and Flu Shots

You can receive your flu shot on the same day as your allergy shot—there is no required waiting interval between these two vaccines. 1

Evidence-Based Recommendation

The ACIP (Advisory Committee on Immunization Practices) explicitly states that inactivated vaccines do not interfere with the immune response to other inactivated vaccines or to live vaccines, and inactivated or live vaccines can be administered simultaneously. 1 Since both allergy immunotherapy (allergen extract injections) and inactivated influenza vaccine (IIV) are inactivated preparations, they can be given together without concern for interference. 1

Practical Implementation Algorithm

If receiving both vaccines on the same day:

  • Administer the allergy shot first, then wait the standard 30-minute observation period required after allergen immunotherapy 1
  • The flu shot can be given either before, during, or after this 30-minute waiting period 1
  • The 30-minute wait is specifically for monitoring potential systemic reactions to the allergy shot, not related to the flu vaccine 1

If scheduling separately:

  • No minimum time interval is required between the two vaccines 1
  • You may receive them on consecutive days or any interval that suits your schedule 1

Critical Safety Considerations

The 30-minute observation period after allergy shots is mandatory because most systemic reactions to allergen immunotherapy occur within this timeframe, though 38% can occur between 30 minutes to 6 hours post-injection. 1 This waiting period applies regardless of whether you receive a flu shot on the same day. 1

Common pitfall to avoid: Do not confuse the post-allergy shot observation requirement with any special precaution related to combining vaccines. 1 The 30-minute wait is standard protocol for allergy immunotherapy alone and is not extended or modified by concurrent flu vaccination. 1

Post-Vaccination Monitoring

After receiving your flu shot, no specific extended observation period is required for egg-allergic persons beyond the standard 15-minute syncope precaution recommended for all vaccines. 1 However, if you're in the office for the mandatory 30-minute allergy shot observation anyway, this provides more than adequate monitoring time for both vaccines. 1

Be aware that local soreness at the flu shot injection site affects 10-64% of patients and lasts less than 2 days—this is a normal inflammatory response, not an allergic reaction. 1, 2 Systemic symptoms like fever, malaise, or myalgia may begin 6-12 hours after flu vaccination and persist 1-2 days, but these are not allergic reactions and do not represent vaccine interference. 1, 2, 3

Special Populations

If you are on beta-blockers: The concern about beta-blockers relates to allergen immunotherapy reactions being more difficult to treat, not to the flu vaccine itself. 1 This does not change the recommendation that both vaccines can be given on the same day. 1

If you have egg allergy: Current ACIP guidelines state that persons with any severity of egg allergy can receive any licensed influenza vaccine appropriate for their age, though those with severe reactions (requiring epinephrine) should receive it in a medical setting supervised by someone who can manage severe allergic reactions. 1 Since you're already in a medical setting for allergy shots with appropriate monitoring, this requirement is automatically satisfied. 1

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Allergic Reactions to Flu Vaccine

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Management of Side Effects in the Elderly After Influenza Vaccination

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.