Cat · Felis catus · typical adult weight 2.50–7.00 kg
Vitamin K1 is dosed at 2.5–5 mg/kg SC q24h (total daily dose) in cats, per Papich MG, Saunders Handbook of Veterinary Drugs, 4th ed, printed p.638 (corpus PDF p.666) - Phytonadione, Small Animal Dosage, Dogs and Cats: 'Treatment of long-acting rodenticides: 2.5-5 mg/kg/day for 3-4 weeks IM, SQ, or PO.' SC route also printed in Plumb's 9th printed p.1025: 'Initial dose of 2.5 - 5 mg/kg PO or SC' and 'label dosage ... 0.25 - 5 mg/kg SC or IM'. BSAVA 10th ed p.434: 'Known inandione (diphacinone) or unknown anticoagulant toxicity: initially 2.5-5 mg/kg s.c. over several sites.' — Plumb's 10th ed (held) printed p.1024-1025 (corpus PDF p.1051-1052), Phytonadione monograph, Dosages [LOCATOR CORRECTED 2026-08-12 — the clause previously here named the Vitamin A monograph]; page located 2026-08-05 from the book's own running heads, verified to name the drug in its body text. — EDITION NOTE 2026-08-06: this rule's Plumb's reference names the 9th edition, which is not held and was never consulted. The held copy is the 10th ed (2023). The Plumb's line was never confirmed against the held edition, so rely on it only as background; any other source named in this citation is unaffected. — SOURCE EDITION: BSAVA Small Animal Formulary, Part A — Canine and Feline — ISBN 9781910443705, https://openlibrary.org/isbn/9781910443705; Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207; Saunders Handbook of Veterinary Drugs — ISBN 9780323244855, https://openlibrary.org/isbn/9780323244855. Vitamin K1 is used in cats for Anticoagulant rodenticide poisoning. Routes documented in cats: SC. A typical adult cat weighs 2.50–7.00 kg. ExoticRx lists 1 cited dose rule for Vitamin K1 in cats, drawn from published veterinary references. Verify against current literature before clinical use.
US trade names: Mephyton, AquaMEPHYTON, Veta-K1
| Route | Dose | Frequency | Duration | Indication | Evidence | Source |
|---|---|---|---|---|---|---|
| SC | 2.5–5 mg/kg | q24h (total daily dose) | 4-6 weeks for long-acting | Anticoagulant rodenticide poisoning | Weak | Papich MG, Saunders Handbook of Veterinary Drugs, 4th ed, printed p.638 (corpus PDF p.666) - Phytonadione, Small Animal Dosage, Dogs and Cats: 'Treatment of long-acting rodenticides: 2.5-5 mg/kg/day for 3-4 weeks IM, SQ, or PO.' SC route also printed in Plumb's 9th printed p.1025: 'Initial dose of 2.5 - 5 mg/kg PO or SC' and 'label dosage ... 0.25 - 5 mg/kg SC or IM'. BSAVA 10th ed p.434: 'Known inandione (diphacinone) or unknown anticoagulant toxicity: initially 2.5-5 mg/kg s.c. over several sites.' — Plumb's 10th ed (held) printed p.1024-1025 (corpus PDF p.1051-1052), Phytonadione monograph, Dosages [LOCATOR CORRECTED 2026-08-12 — the clause previously here named the Vitamin A monograph]; page located 2026-08-05 from the book's own running heads, verified to name the drug in its body text. — EDITION NOTE 2026-08-06: this rule's Plumb's reference names the 9th edition, which is not held and was never consulted. The held copy is the 10th ed (2023). The Plumb's line was never confirmed against the held edition, so rely on it only as background; any other source named in this citation is unaffected. — SOURCE EDITION: BSAVA Small Animal Formulary, Part A — Canine and Feline — ISBN 9781910443705, https://openlibrary.org/isbn/9781910443705; Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207; Saunders Handbook of Veterinary Drugs — ISBN 9780323244855, https://openlibrary.org/isbn/9780323244855 |
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 |
|---|---|---|---|
| 2.5 | SC | BSAVA Small Animal Formulary, 10th ed — Part A (Canine and Feline)p.450 | in toxicity or vitamin K1 deficiency: initially 2.5 mg/kg s.c. in several sites, then 1-2.5 mg/kg in divided doses p.o. q8-12h for 5-7 d |
| 1–2.5 | IV | BSAVA Small Animal Formulary, 10th ed — Part A (Canine and Feline)p.450 | deficiency: initially 2.5 mg/kg s.c. in several sites, then 1-2.5 mg/kg in divided doses p.o. q8-12h for 5-7 days. • Known 2nd generation coumarin (bro |
| 5 | SC | BSAVA Small Animal Formulary, 10th ed — Part A (Canine and Feline)p.450 | n 2nd generation coumarin (brodifacoum) toxicity: initially 5 mg/kg s.c. in several sites, then 2.5 mg/kg p.o. q12h for 3 weeks, then re-evaluate |
| 2.5 | PO |
Need the exact dose for your patient?
These ranges are per kg. Enter your cat's weight to get the precise dose and draw-up volume — unit and concentration math done for you.
Essential cofactor for hepatic carboxylation of clotting factors II, VII, IX, X. Reverses vitamin K-dependent coagulopathy from anticoagulant rodenticides.
Give PO with fatty food (fat-soluble). SC preferred over IM (hematoma risk) or IV (anaphylaxis risk). Long-acting rodenticides (brodifacoum) require 4-6 weeks treatment. Monitor PT.
Species-specific contraindications and adverse-reaction reports for cats may differ from canine / feline reference data — consult the primary citations listed with each rule.
Vitamin K1 dose range in cats, with cited source references: SC 2.5–5 mg/kg q24h (total daily dose). Reference ranges from cited sources — verify against current literature before clinical use.
Documented routes for Vitamin K1 in cats: SC.
Cited course lengths for Vitamin K1 in cats include: 4-6 weeks for long-acting. Duration depends on the indication — match it to the specific dose rule in the table above.
Vitamin K1 is indicated in cats for: Anticoagulant rodenticide poisoning.
These are general warnings for Vitamin K1 across species; consult the cat dosing table above for species-specific guidance. Give PO with fatty food (fat-soluble). SC preferred over IM (hematoma risk) or IV (anaphylaxis risk). Long-acting rodenticides (brodifacoum) require 4-6 weeks treatment. Monitor PT.
Why a species-specific page? Vitamin K1 pharmacokinetics differ across species: dose ranges, intervals, and route preferences are not interchangeable. Cross-extrapolation from canine doses is unsafe in cats — 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.
| xicity: initially 2.5-5 mg/kg s.c. over several sites. Then 2.5 mg/kg p.o. divided q8-12h for 3-4 weeks. Re-evaluate coagulation status 2 days after stopping t |
| 2.5–5 | SC | BSAVA Small Animal Formulary, 10th ed — Part A (Canine and Feline)p.450 | (diphacinone) or unknown anticoagulant toxicity: initially 2.5-5 mg/kg s.c. over several sites. Then 2.5 mg/kg p.o. divided q8-12h for 3-4 weeks. Re- |
| 0.5–1 | SC | BSAVA Small Animal Formulary, 10th ed — Part A (Canine and Feline)p.450 | times as above. • Liver disease (pre-biopsy): 0.5-1.0 mg/kg s.c. q12h. After 1-2 days re-evaluate coagulation time and if normal proceed w |
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.