Dog · Canis lupus familiaris · typical adult weight 2.00–80.00 kg
Cyclophosphamide is dosed at 200–300 mg/m2 PO q21d or 50 mg/m2 daily x4 days/week in dogs, per Plumb's Veterinary Drug Handbook, 10th ed (2023, held copy; the original seed cited the 9th, which was never consulted) — Plumb's 10th ed (held) printed p.318, Cyclophosphamide monograph spanning p.318-321; page located 2026-08-05 from the book's own running heads, verified to name the drug in its body text. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207 — Plumb's Veterinary Drug Handbook, 10th ed (held), Cyclophosphamide monograph, printed p.320 (corpus PDF p.347), DOGS: "Antineoplastic agent: Often used as part of a multidrug chemotherapy protocol (eg, COP, CHOP) […]" Same monograph, printed p.318, Uses/Indications: "Most clinicians do not consider cyclophosphamide for initial use as an immunosuppressive agent for […]" [INDICATION NARROWED 2026-08-12, two readers — the immune-mediated half is contradicted by the monograph.]. Cyclophosphamide is used in dogs for Lymphoma — antineoplastic, as part of a multidrug protocol (eg COP, CHOP). Routes documented in dogs: PO. A typical adult dog weighs 2.00–80.00 kg. ExoticRx lists 1 cited dose rule for Cyclophosphamide in dogs, drawn from published veterinary references. Verify against current literature before clinical use.
US trade names: Cytoxan
| Route | Dose | Frequency | Duration | Indication | Evidence | Source |
|---|---|---|---|---|---|---|
| PO | 200–300 mg/m2 |
| q21d or 50 mg/m2 daily x4 days/week |
| Per protocol |
| Lymphoma — antineoplastic, as part of a multidrug protocol (eg COP, CHOP) |
| Strong |
| Plumb's Veterinary Drug Handbook, 10th ed (2023, held copy; the original seed cited the 9th, which was never consulted) — Plumb's 10th ed (held) printed p.318, Cyclophosphamide monograph spanning p.318-321; page located 2026-08-05 from the book's own running heads, verified to name the drug in its body text. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207 — Plumb's Veterinary Drug Handbook, 10th ed (held), Cyclophosphamide monograph, printed p.320 (corpus PDF p.347), DOGS: "Antineoplastic agent: Often used as part of a multidrug chemotherapy protocol (eg, COP, CHOP) […]" Same monograph, printed p.318, Uses/Indications: "Most clinicians do not consider cyclophosphamide for initial use as an immunosuppressive agent for […]" [INDICATION NARROWED 2026-08-12, two readers — the immune-mediated half is contradicted by the monograph.] |
Every held source for this drug and species, as printed. Where they differ, both are shown — the choice is yours, not ours.
The sources disagree for this combination. The ranges below do not overlap on a comparable route. This is not an error in one of them — published veterinary references differ, and reconciling them for a particular patient is a clinical judgement.
| Dose (mg/kg) | Route | Source | As printed |
|---|---|---|---|
| 1 | PO | BSAVA Small Animal Formulary, 10th ed — Part A (Canine and Feline)p.119 | • Multiple myeloma in patients refractory to melphalan: 1 mg/kg p.o. q24h. • Macroglobulinaemia in patients refractory to chlorambucil: 1 mg |
| 2.2 | — | Papich Saunders Handbook of Veterinary Drugs, 4th edp.221 | • Anticancer dose: 50 mg/m2 (approx. 2.2 mg/kg) q48h or once daily 4 days/week |
| 0.3 | PO | Papich Saunders Handbook of Veterinary Drugs, 4th edp.221 | q24h, PO (approximately 0.3 mg/kg). |
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Prodrug activated by hepatic CYP enzymes to form phosphoramide mustard, which alkylates DNA, cross-linking strands and inhibiting replication.
Sterile hemorrhagic cystitis from metabolite acrolein — concurrent furosemide/mesna and adequate hydration recommended. Myelosuppression. Handler precautions. Also used for immune-mediated diseases.
Species-specific contraindications and adverse-reaction reports for dogs may differ from canine / feline reference data — consult the primary citations listed with each rule.
Cyclophosphamide dose range in dogs, with cited source references: PO 200–300 mg/m2 q21d or 50 mg/m2 daily x4 days/week. Reference ranges from cited sources — verify against current literature before clinical use.
Documented routes for Cyclophosphamide in dogs: PO.
Cited course lengths for Cyclophosphamide in dogs include: Per protocol. Duration depends on the indication — match it to the specific dose rule in the table above.
Cyclophosphamide is indicated in dogs for: Lymphoma — antineoplastic, as part of a multidrug protocol (eg COP, CHOP).
These are general warnings for Cyclophosphamide across species; consult the dog dosing table above for species-specific guidance. Sterile hemorrhagic cystitis from metabolite acrolein — concurrent furosemide/mesna and adequate hydration recommended. Myelosuppression. Handler precautions. Also used for immune-mediated diseases.
Why a species-specific page? Cyclophosphamide pharmacokinetics differ across species: dose ranges, intervals, and route preferences are not interchangeable. Cross-extrapolation from canine doses is unsafe in dogs — 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.
| 2.2 |
| PO |
| Papich Saunders Handbook of Veterinary Drugs, 4th edp.221 |
| • Immunosuppressive therapy: Dogs: 50 mg/m2 q48h PO or 2.2 mg/kg once daily |
| 10 | — | Papich Saunders Handbook of Veterinary Drugs, 4th edp.221 | • Pulse therapy: 200-250 mg/m2 (10 mg/kg), once every 3 weeks. Dividing the |
| Dose (mg/m2) | Route | Source | As printed |
|---|---|---|---|
| 50 | — | Papich Saunders Handbook of Veterinary Drugs, 4th edp.221 | • Anticancer dose: 50 mg/m2 (approx. 2.2 mg/kg) q48h or once daily 4 days/week |
| 150–300 | PO | Papich Saunders Handbook of Veterinary Drugs, 4th edp.221 | PO. Alternatively, some protocols use 150-300 mg/m2 IV and repeat in 21 days. |
| 10–15 | — | Papich Saunders Handbook of Veterinary Drugs, 4th edp.221 | • Metronomic dose (continuous administration to suppress T cells): 10-15 mg/m2, |
| 50 | PO | Papich Saunders Handbook of Veterinary Drugs, 4th edp.221 | • Immunosuppressive therapy: Dogs: 50 mg/m2 q48h PO or 2.2 mg/kg once daily |
| 200–250 | — | Papich Saunders Handbook of Veterinary Drugs, 4th ed |
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.
| • Pulse therapy: 200-250 mg/m2 (10 mg/kg), once every 3 weeks. Dividing the |
| 250 | — | Papich Saunders Handbook of Veterinary Drugs, 4th edp.221 | 250 mg/m2 dose into three treatments, over three days, may reduce risk of sterile |