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Cited by 125Syphilis Diagnosis and TreatmentHistorical Medical Research and TreatmentsVector-borne infectious diseases

Doxycycline compared with benzathine penicillin for the treatment of early syphilis.

Ghanem, K. G., Erbelding, E. J., Cheng, W. W., Rompalo, A. M.·2006·Clinical Infectious Diseases
DOI 10.1086/500406
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Abstract

BACKGROUND: Doxycycline is the preferred recommended second-line agent for the treatment of syphilis, although efficacy data from controlled trials are lacking. We compared the serological responses of patients with early syphilis treated with doxycycline with the responses of patients treated with benzathine penicillin G (BPG). METHODS: All patients who received a diagnosis of early syphilis attending 2 public sexually transmitted disease clinics in Baltimore, Maryland, who were treated with doxycycline (100 mg orally, twice daily for 14 days) between October 1993 and June 2000 were eligible. Patients treated with BPG (a single dose of 2.4 million units intramuscularly) were selected as the control group. Inclusion criteria included a clinician-recorded diagnosis of primary, secondary, or early latent syphilis with reactive serological test results at the time of diagnosis and at least 1 follow-up serological test titer. Serological failure was defined as lack of a 4-fold drop in rapid plasma reagin titer 270-400 days after treatment, or a 4-fold increase in titer 30-400 days after therapy. RESULTS: During the study period, 1558 patients were treated for early syphilis, and 87 received doxycycline. Of those treated with doxycycline, 34 met the inclusion criteria. Seventy-three patients from a randomly selected group of 200 age-matched individuals treated with BPG met the inclusion criteria. There were 4 patients with serological failure in the BPG group (5.5%; 95% confidence interval [CI], 1.6%-13.8%) and 0 patients with serological failure in the doxycycline group (0%; 95% CI, 0%-10.3%; P=.2). The median times to successful serological responses for patients in the doxycycline and BPG groups were 106 days (95% CI, 75-149 days) and 137 days (95% CI, 111-172 days), respectively (P=.6). CONCLUSION: Doxycycline appears to be an effective agent for the treatment of early syphilis.

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  • Doxycycline 100 mg once or twice daily for 14 days is effective for syphilis.

    “although 100 mg once (OD) or twice daily (BD) for 14 days is effective,92–96”

    From BASHH UK guidelines for the management of syphilis 2024 (2024) · cites this paper as [93]

    The Methods and Results report treatment of early syphilis with doxycycline 100 mg twice daily for 14 days, with no serological failures among 34 eligible patients. The paper does not establish the effectiveness of 100 mg once daily for exactly 14 days; it describes a separate uncontrolled study using once-daily dosing for 10–15 days. (LLM, conf=0.87)

    Experimental — accuracy not yet measured

  • Doxycycline (100 mg orally 2 times/day for 14 days) can be effective for nonpregnant persons with penicillin allergy who have primary or secondary syphilis.

    “Doxycycline (100 mg orally 2 times/day for 14 days) (600,601) and tetracycline (500 mg orally 4 times/day for 14 days) have been used for years and can be effective.”

    From Sexually Transmitted Infections Treatment Guidelines, 2021 (2021) · cites this paper as [600]

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Research works printed but not linked: 2

  1. Rajam RV, Rangiah RN, Somini C, Krishnamoorthy C. Tetracycline (achromycin) in venereal diseases. Antiseptic Madras 1956; 53:9-19.
  2. Kaplan EL, Meier P. Non-parametric estimation from incomplete ob- servations. J Am Stat Assoc 1958; 3:457-81.

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Authors
Ghanem, K. G., Erbelding, E. J., Cheng, W. W., & Rompalo, A. M.
Affiliations
  • Johns Hopkins University (US)
  • Stanford Medicine (US)
Corresponding author
Ghanem, K. G.
ORCID
Venue
Clinical Infectious Diseases
Publisher
Oxford University Press (OUP)
Published
2006-03-15
Volume
42
Issue
6
Pages
e45-e49
ISSN
  • 1058-4838 (ISSN-L)
  • 1537-6591
DOI
10.1086/500406
OpenAlex
W2150139804
Cited by
125
References
17
Citations by year
2026: 1 · 2025: 6 · 2024: 5 · 2023: 13 · 2022: 5 · 2021: 3 · 2020: 9 · 2019: 8 · 2018: 4 · 2017: 7 · 2016: 7 · 2015: 14 · 2014: 9 · 2013: 3 · 2012: 5
FWCI
1.99
Type
journal article
Language
en
Open access
closed
Locations
  • Clinical Infectious Diseases (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Institutes of Health
  • National Institute of Allergy and Infectious Diseases (R01AI045724)
Topics
  • Health Sciences › Medicine › Physiology › Syphilis Diagnosis and Treatment
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Historical Medical Research and Treatments
  • Life Sciences › Immunology and Microbiology › Parasitology › Vector-borne infectious diseases
Keywords
early syphilis, doxycycline, benzathine penicillin G, syphilis treatment, serological response, RPR titer, second-line therapy, sexually transmitted infections
MeSH terms
Adolescent, Adult, Anti-Bacterial Agents, Doxycycline, Drug Evaluation, Female, Humans, Male, Penicillin G Benzathine, Retrospective Studies, Syphilis, Treatment Outcome

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