Related Experiment Video

Updated: Aug 21, 2026

Multiplex Therapeutic Drug Monitoring by Isotope-dilution HPLC-MS/MS of Antibiotics in Critical Illnesses
11:17

Multiplex Therapeutic Drug Monitoring by Isotope-dilution HPLC-MS/MS of Antibiotics in Critical Illnesses

Published on: August 30, 2018

The Impact of Doxycycline Post-Exposure Prophylaxis on Antibiotic Use at a Boston Sexual Health Clinic

Rachel Mittelstaedt, David Helekal, Madeleine C Kline

    Medrxiv : the Preprint Server for Health Sciences
    |August 20, 2026
    PubMed
    Abstract

    Insights

    Doxycycline post-exposure prophylaxis (doxy-PEP) may increase antibiotic use in users, potentially driving antimicrobial resistance. However, it also reduces sexually transmitted infections, which could decrease resistance pressure in non-users.

    Area of Science:

    • Infectious Diseases
    • Pharmacology
    • Public Health

    Background:

    • Doxycycline post-exposure prophylaxis (doxy-PEP) is effective in reducing bacterial sexually transmitted infections (STIs) among men who have sex with men and transgender women (MSMTW).
    • A key concern with doxy-PEP is its potential to drive antimicrobial resistance (AMR) by altering antibiotic usage patterns.
    • Understanding the impact of doxy-PEP on antibiotic prescription rates is crucial for assessing its overall effect on AMR selection.

    Purpose of the Study:

    • To evaluate the direct, indirect, and combined effects of doxy-PEP implementation on antibiotic prescription rates.
    • To assess how doxy-PEP influences antibiotic use among MSMTW receiving HIV pre-exposure prophylaxis.

    Main Methods:

    • Retrospective electronic medical record review of antibiotic prescriptions at a sexual health clinic.
    • Analysis of data from January 1, 2023, to December 27, 2025.
    • Application of Bayesian negative binomial regression to model antibiotic prescription rates.

    Main Results:

    • The overall antibiotic prescription rate in the cohort increased 1.4-fold after doxy-PEP implementation.
    • Doxy-PEP users had significantly higher antibiotic prescription rates compared to non-users (3.40 times higher).
    • For every 100 doxy-PEP starts, the total antibiotic prescription rate decreased by 10%, indicating indirect effects on non-users.

    Conclusions:

    • Doxy-PEP use is associated with increased antibiotic prescription rates in users, potentially increasing selection for antibiotic-resistant bacteria.
    • Reductions in STI incidence due to doxy-PEP may decrease selective pressure for resistant organisms in non-users.
    • The net effect of doxy-PEP on AMR requires careful consideration of both direct and indirect impacts on antibiotic use and resistance selection.

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