Work

Comparative efficacy of once-daily versus twice-daily doxycycline regimens in dogs naturally infected with Ehrlichia canis: A randomized clinical trial

Year: 2026

Type: article

Abstract: • BID doxycycline significantly reduces treatment duration. • Divided dosing accelerates early platelet recovery. • Standard 28-day therapy may fail to clear E. canis DNA. • Treat-to-target protocol ensures complete molecular cure. This prospective, randomized clinical trial compared the therapeutic efficacy and rate of platelet recovery of doxycycline 10 mg/kg once daily (SID) (Group A, n=17) versus 5 mg/kg twice daily (BID) (Group B, n=12) in 29 dogs naturally infected with Ehrlichia canis . Using a "treat-to-target" protocol that mandated both molecular clearance and platelet normalization prior to cessation, results showed that while both regimens achieved 100% molecular clearance, the BID regimen demonstrated significantly more rapid hematological recovery (P < 0.05 at Days 7 and 14) and required a significantly shorter median treatment duration (28.5 days vs. 39.0 days; P = 0.015). Notably, delayed molecular clearance (>28 days) was observed exclusively in the SID group, and post-treatment recrudescence was detected in two dogs at Day 98. We conclude that the 5 mg/kg BID protocol offers superior pharmacodynamic performance, and a "treat-to-target" strategy involving long-term monitoring is recommended over a fixed 28-day course to ensure complete clinical and parasitological resolution.

Source: Veterinary and Animal Science

DOI: 10.1016/j.vas.2026.100661

Authors: Mookmanee Taechikantaphat, Areerat Kongchareon, Pruksa Julapanthong, Ladawan Sariya, Walasinee Sakcamduang

Institution: Mahidol University

Language: English

Topic: Vector-borne infectious diseases

Subfield: Parasitology

Field: Immunology and Microbiology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,780