Vitamin K1
Vitamin K1 (phytonadione) is an essential fat-soluble vitamin used primarily to treat and prevent bleeding disorders caused by vitamin K deficiency. It is commonly administered to reverse excessive anticoagulation from warfarin therapy and to prevent hemorrhagic disease in newborns. This medication works by supporting the body's natural blood clotting mechanisms.
Vitamin K1 is used to treat and prevent bleeding by supporting normal blood clotting, particularly in cases of deficiency or warfarin overdose.
Key facts at a glance
- ATC
- B02BA01
- RxNorm
- 8308
- Generic
- Vitamin K1
- Class
- atc-b02
- Brands
- Infuvite, Infuvite Pediatric, Veta-K1, Mephyton
- Availability
- rx
- Lactation
- unknown
- Routes
- oral, sublingual
- Forms
- injection, prefilled syringe, solution, tablet, capsule
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 2.5 to 25 mg daily
- Maximum
- consult physician
- Frequency
- once daily or divided
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 2.5 to 5 mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 2.5 to 15 mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
8 groupspregnancy
all trimestersuse lowest effective dose
use only when clearly needed for vitamin K deficiency or anticoagulant reversal benefits outweigh potential risks
monitor maternal and fetal status
Use with caution and monitor for adverse effects.
lactation
breastfeedingno adjustment needed
considered compatible with breastfeeding; vitamin K supplementation may be recommended for exclusively breastfed infants
standard infant monitoring
geriatric
over 65no specific adjustment required
standard dosing applies; consider renal and hepatic function
monitor coagulation parameters and organ function
pediatric_age
neonatesage-appropriate dosing required
single intramuscular dose of 0.5-1mg recommended at birth to prevent vitamin K deficiency bleeding
monitor for bleeding signs
pediatric_age
infants childrenweight-based dosing
used for treatment of vitamin K deficiency; dosing based on clinical indication and weight
monitor coagulation parameters
renal_impairment
all stagesno dose adjustment typically required
standard dosing for vitamin K deficiency or anticoagulant reversal
monitor coagulation parameters
hepatic_impairment
mild moderatemay require higher doses
vitamin K metabolism may be impaired; higher doses may be needed for response
monitor coagulation parameters and liver function
Use with caution and monitor for adverse effects.
hepatic_impairment
severeuse with caution and close monitoring
limited efficacy in severe liver disease due to impaired gamma-carboxylation of clotting factors
frequent coagulation monitoring required
Use with caution and monitor for adverse effects.
Statistics and clinical data
Drug class
Vitamin K1 belongs to the vitamin K group of compounds
Common uses
Primary therapeutic indications for Vitamin K1
FDA approval year
FDA has approved phytonadione formulations since the 1960s
Available formulations
Available dosage forms for clinical use
Treatment and prevention of bleeding due to vitamin K deficiency; reversal of warfarin-induced anticoagulation; prevention and treatment of hemorrhagic disease of the newborn; management of hypoprothrombinemia from various causes including malabsorption, liver disease, or prolonged antibiotic use.
Vitamin K1 serves as an essential cofactor for the enzyme gamma-glutamyl carboxylase, which is required for the synthesis of vitamin K-dependent clotting factors (II, VII, IX, X) and anticoagulant proteins (C and S). This carboxylation reaction enables these proteins to bind calcium and participate effectively in the coagulation cascade.
Available in oral, intravenous, intramuscular, and subcutaneous formulations; IV administration requires slow infusion due to anaphylaxis risk; efficacy monitoring via INR is recommended when used with warfarin; dietary vitamin K intake can affect warfarin response; stored in the liver and released as needed for clotting factor synthesis.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 24, 2026. · Read our editorial policy