Equine · Equus caballus · typical adult weight 350.00–700.00 kg
Azithromycin is dosed at 10 mg/kg PO q24h x5 days then q48h in horses, per Giguere S. Treatment of infections caused by Rhodococcus equi. Vet Clin North Am Equine Pract. 2017;33(1):67-85. PMID: 41600728; Giguere S, Jacks S, Roberts GD, Hernandez J, Long MT, Ellis C. Retrospective Comparison of Azithromycin, Clarithromycin, and Erythromycin for the Treatment of Foals with Rhodococcus equi Pneumonia. J Vet Intern Med. 2004;18(4):568-573. doi:10.1892/0891-6640(2004)18<568:rcoaca>2.0.co;2 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.149 (2026-08-01). — Plumb's 10th ed (held) printed p.122, Azithromycin monograph spanning p.120-122; page located 2026-08-05 from the book's own running heads, and carries this exact dose under the matching species heading. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207. Azithromycin is used in horses for Rhodococcus equi in foals (with rifampin). Routes documented in horses: PO. A typical adult horse weighs 350.00–700.00 kg. ExoticRx lists 1 cited dose rule for Azithromycin in horses, drawn from published veterinary references. Verify against current literature before clinical use.
US trade names: Zithromax
| Route | Dose | Frequency | Duration | Indication | Evidence |
|---|
| Source |
|---|
| PO | 10 mg/kg | q24h x5 days then q48h | 4-12 weeks | Rhodococcus equi in foals (with rifampin) | Strong | Giguere S. Treatment of infections caused by Rhodococcus equi. Vet Clin North Am Equine Pract. 2017;33(1):67-85. PMID: 41600728; Giguere S, Jacks S, Roberts GD, Hernandez J, Long MT, Ellis C. Retrospective Comparison of Azithromycin, Clarithromycin, and Erythromycin for the Treatment of Foals with Rhodococcus equi Pneumonia. J Vet Intern Med. 2004;18(4):568-573. doi:10.1892/0891-6640(2004)18<568:rcoaca>2.0.co;2 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.149 (2026-08-01). — Plumb's 10th ed (held) printed p.122, Azithromycin monograph spanning p.120-122; page located 2026-08-05 from the book's own running heads, and carries this exact dose under the matching species heading. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207 |
Every held source for this drug and species, as printed. Where they differ, both are shown — the choice is yours, not ours.
| Dose (mg/kg) | Route | Source | As printed |
|---|---|---|---|
| 10 | PO | Papich Saunders Handbook of Veterinary Drugs, 4th edp.97 | • For Rhodococcus equi: 10 mg/kg q24h, PO initially for 5 days, then q48h after a |
Figures are transcribed from the cited page or table of each held edition and are shown for reference only. They are not dose recommendations, they do not feed the calculator, and none has been reviewed by a veterinarian.
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Binds to 50S ribosomal subunit, inhibiting bacterial protein synthesis. Concentrates in tissues with long half-life.
CONTRAINDICATED orally in rabbits and guinea pigs (fatal dysbiosis). May cause GI upset. Long tissue half-life means prolonged effect after discontinuation.
Species-specific contraindications and adverse-reaction reports for horses may differ from canine / feline reference data — consult the primary citations listed with each rule.
Azithromycin dose range in horses, with cited source references: PO 10 mg/kg q24h x5 days then q48h. Reference ranges from cited sources — verify against current literature before clinical use.
Documented routes for Azithromycin in horses: PO.
Cited course lengths for Azithromycin in horses include: 4-12 weeks. Duration depends on the indication — match it to the specific dose rule in the table above.
Azithromycin is indicated in horses for: Rhodococcus equi in foals (with rifampin).
These are general warnings for Azithromycin across species; consult the horse dosing table above for species-specific guidance. CONTRAINDICATED orally in rabbits and guinea pigs (fatal dysbiosis). May cause GI upset. Long tissue half-life means prolonged effect after discontinuation.
Why a species-specific page? Azithromycin pharmacokinetics differ across species: dose ranges, intervals, and route preferences are not interchangeable. Cross-extrapolation from canine doses is unsafe in horses — the rules above are the citations specific to this species, not generic recommendations.
Sourced from published veterinary references; awaiting credentialed clinical reviewer. See our editorial process. Reference only — not veterinary advice.