Can you take azithromycin (Zithromax) if you are allergic to doxycycline?

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: April 7, 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.

From the Guidelines

If you are allergic to doxycycline, you can generally take azithromycin as these are different classes of antibiotics with different chemical structures, and cross-reactivity between these classes is rare, as indicated by the guidelines from the Centers for Disease Control and Prevention 1. Doxycycline is a tetracycline antibiotic, while azithromycin is a macrolide antibiotic. However, you should always inform your healthcare provider about any medication allergies before starting azithromycin. The typical adult dose of azithromycin can vary depending on the infection being treated, but a common dose is 1 g orally in a single dose, as recommended by the guidelines 1. Some key points to consider when taking azithromycin include:

  • Take azithromycin as prescribed, usually once daily, with or without food (though some people experience less stomach upset when taking it with food)
  • If you experience symptoms like rash, itching, swelling, severe dizziness, or trouble breathing after taking azithromycin, seek medical attention immediately as these could indicate an allergic reaction to this medication as well. It's also worth noting that older guidelines, such as those from 1998 1, also support the use of azithromycin as an alternative to doxycycline, but the most recent and highest quality study should be prioritized 1.

From the Research

Antibiotic Allergies and Cross-Reactivity

  • The provided studies do not directly address the question of taking azithromycin if one is allergic to doxycycline 2, 3, 4, 5, 6.
  • However, they discuss the importance of understanding antibiotic allergies, cross-reactivity, and proper antibiotic selection in various settings.
  • Azithromycin is a macrolide antibiotic, and doxycycline is a tetracycline antibiotic, which are different classes of antibiotics.
  • The studies suggest that drug challenge is the preferred method for evaluating macrolide allergy 2 and that cross-reactivity among drugs can be mediated by immunologic or non-immunologic mechanisms 4.
  • It is essential to note that the provided studies focus on penicillin allergies, cephalosporin allergies, and cross-reactivity, rather than specifically addressing azithromycin and doxycycline.

Considerations for Antibiotic Selection

  • When selecting an antibiotic, it is crucial to consider the patient's allergy history and potential cross-reactivity with other antibiotics 3, 5, 6.
  • Clinicians should be aware of the different types of penicillin-allergic reactions and choose antibiotics that do not cross-react with penicillins or beta-lactams 3.
  • The studies emphasize the importance of proactive evaluation and management of antibiotic allergies to reduce patient morbidity and mortality 2, 5, 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Antibiotic selection in the penicillin-allergic patient.

The Medical clinics of North America, 2006

Research

The 3 Cs of Antibiotic Allergy-Classification, Cross-Reactivity, and Collaboration.

The journal of allergy and clinical immunology. In practice, 2017

Research

Understanding Penicillin Allergy, Cross-reactivity, and Antibiotic Selection in the Preoperative Setting.

The Journal of the American Academy of Orthopaedic Surgeons, 2022

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.