Essential cofactor for hepatic carboxylation of coagulation factors II, VII, IX, and X; directly reverses vitamin K antagonist (anticoagulant rodenticide) poisoning
At a glance
Class
Fat-soluble vitamin / Coagulation factor cofactor
Storage
Store below 25°C, protect from light; give PO with fatty food to enhance absorption
Dosing
Anticoagulant rodenticide toxicosis
Frequency
BID (initially); then SID once stable
Max dose
250 mg/dose; 500 mg/day
Duration: First-gen warfarin: 7 days; Second-gen (brodifacoum): 4–6 weeks; recheck PT 48–72h after stopping
Anticoagulant rodenticide toxicosis
Frequency
BID initially; then SID
Max dose
50 mg/dose; 100 mg/day
Duration: Same as dog; duration depends on rodenticide generation
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet.
Find a vet near you →Safety
Absolute contraindications — do not use
Adverse effects
Common
Pain at SC/IM injection site
Serious
Anaphylactoid reaction (IV use)
Hematoma at injection site
PT/PTT (baseline, 48h after starting, 48–72h after stopping)Signs of bleeding
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet.
Find a vet near you →Interactions
No documented interactions.
Brands
India
Phytomenadione IP
Neon Labs
FAQs
Frequently asked questions
›What is Vitamin K1 (Phytonadione)?
Vitamin K1 (Phytonadione) is a fat-soluble vitamin / coagulation factor cofactor used in pets. Essential cofactor for hepatic carboxylation of coagulation factors II, VII, IX, and X; directly reverses vitamin K antagonist (anticoagulant rodenticide) poisoning
›What is Vitamin K1 (Phytonadione) used for in pets?
Vitamin K1 (Phytonadione) is used in veterinary medicine for: Anticoagulant rodenticide toxicosis.
›What is the Vitamin K1 (Phytonadione) dose for dogs?
For dogs, Vitamin K1 (Phytonadione) is typically dosed as follows — Anticoagulant rodenticide toxicosis: 2.5–5 mg/kg PO/SC/IM BID (initially); then SID once stable. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What is the Vitamin K1 (Phytonadione) dose for cats?
For cats, Vitamin K1 (Phytonadione) is typically dosed as follows — Anticoagulant rodenticide toxicosis: 2.5–5 mg/kg PO/SC/IM BID initially; then SID. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What are the side effects of Vitamin K1 (Phytonadione)?
Common: Pain at SC/IM injection site. Serious (call your vet immediately): Anaphylactoid reaction (IV use), Hematoma at injection site.
›Does Vitamin K1 (Phytonadione) need a prescription?
Yes. Vitamin K1 (Phytonadione) is a prescription medication and should only be administered under veterinary supervision.
›When should Vitamin K1 (Phytonadione) not be used?
Do not use Vitamin K1 (Phytonadione) if: IV injection (anaphylaxis risk).
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet.
Find a vet near you →References
CDSCO approvals (India) — 1
Injection of Vitamin A, D, B
M/s Roche Products Bombay · Approved 1970 April
Vitamin Preparation.
Source: CDSCO Veterinary Drug Approval Registry (1969–2026)
References
The PetCare.AI drug reference is built from 13 authoritative sources cited across 580 drug monographs.
Textbooks & handbooks — 5
- Plumb's Veterinary Drug Handbook
- Withrow & MacEwen's Small Animal Clinical Oncology
- Merck Veterinary Manual
- NRC Nutrient Requirements of Dogs and Cats
- Veterinary Pharmacology and Therapeutics (Riviere & Papich)
Clinical guidelines & consensus — 4
- ASPCA Animal Poison Control Center Guidelines
- AAHA Diabetes Management Guidelines
- ASPCA Poison Control Guidelines
- RECOVER CPR Guidelines
Journals & peer-reviewed studies — 2
- EPIC Study (J Vet Intern Med 2016)
- JVIM FAT CAT Study
Regulatory & approvals — 1
- CDSCO Veterinary Drug Approval Registry (1969–2026)
Databases — 1
- Washington State University VCPL MDR1 Database