Dosing & Uses
Dosage Forms & Strengths
tablet
- 100mcg
- 5mg
injection emulsion
- 2mg/mL
- 10mg/mL
Nutritional Supplementation
Recommended daily intake (RDA)
Males: 120 mcg/day PO
Females: 90 mcg/day PO
Hypoprothrombinemia Due To Drugs or Factors Limiting Absorption or Synthesis
2.5-10 mg PO/SC; may be increased PRN to 25 mg or, rarely, to 50 mg; may be repeated in 12-48 hours
Reversal of Warfarin Effects
Omit 1-2 doses, or hold warfarin; monitor INR and adjust warfarin dose accordingly
INR 4.5-10, no bleeding: 2012 ACCP guidelines suggest against routine use; 2008 ACCP guidelines suggest considering vitamin K1 (phytonadione) 1-2.5 mg PO once
INR >10, no bleeding: 2012 ACCP guidelines recommend vitamin K1 PO (dose not specified); 2008 ACCP guidelines suggest 2.5-5 mg PO once; INR reduction observed within 24-48 hr, monitor INR and give additional vitamin K if needed
Minor bleeding, any elevated INR: Consider 2.5-5 mg PO once; may repeat if needed after 24 hr
Major bleeding, any elevated INR: 2012 ACCP guidelines recommend prothrombin complex concentrate, human (PCC, Kcentra) plus vitamin K1 5-10 mg IV (dilute in 50 mL IV fluid and infuse over 20 min)
NOTE: High vitamin K doses (ie, 10 mg or more) may cause warfarin resistance for a week or more; consider using heparin, LMWH, or direct thrombin inhibitors to provide adequate thrombosis prophylaxis in clinical conditions requiring chronic anticoagulation therapy (eg, atrial fibrillation)
Dosing Considerations
PO dose may be repeated in 12-48 hr and SC/IV/IM dose in 6-8 hr if necessary
Avoid IM route; increases risk of hematoma formation
Oral route more effective than SC route in nonbleeding patients in warfarin associated coagulopathy
IV rate not to exceed 1 mg/min
May use IV route in selected nonbleeding patients; use IV route in patients with major bleeding due to warfarin associated coagulopathy
Use of high vitamin K doses (10-15 mg) may cause warfarin resistance for ≥1 week
Dosage Forms & Strengths
tablet
- 100mcg
- 5mg
injection emulsion
- 2mg/mL
- 10mg/mL
Nutritional Supplementation
RDA
0-6 months: 2 mcg/day
6-12 months: 2.5 mcg/day
1-3 years: 30 mcg/day
4-8 years: 55 mcg/day
9-13 years: 60 mcg/day
14-18 years: 75 mcg/day
Hemorrhagic Disease of the Newborn
Prophylaxis: 0.5-1 mg IM within 1 hr of birth
Treatment: 1 mg/dose/day SC; my require higher doses if mother has been receiving oral anticoagulants
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (0)
Serious - Use Alternative (0)
Monitor Closely (40)
- aspirin rectal
aspirin rectal increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .
- aspirin/citric acid/sodium bicarbonate
aspirin/citric acid/sodium bicarbonate increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- choline magnesium trisalicylate
choline magnesium trisalicylate increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .
- erythromycin base
erythromycin base will decrease the level or effect of vitamin K1 (phytonadione) by altering intestinal flora. Applies only to oral form of both agents. Use Caution/Monitor.
- erythromycin ethylsuccinate
erythromycin ethylsuccinate will decrease the level or effect of vitamin K1 (phytonadione) by altering intestinal flora. Applies only to oral form of both agents. Use Caution/Monitor.
- erythromycin lactobionate
erythromycin lactobionate will decrease the level or effect of vitamin K1 (phytonadione) by altering intestinal flora. Applies only to oral form of both agents. Use Caution/Monitor.
- erythromycin stearate
erythromycin stearate will decrease the level or effect of vitamin K1 (phytonadione) by altering intestinal flora. Applies only to oral form of both agents. Use Caution/Monitor.
- fennel
fennel increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- feverfew
feverfew increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- flurbiprofen
flurbiprofen increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- forskolin
forskolin increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- garlic
garlic increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- ginger
ginger increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- ginkgo biloba
ginkgo biloba increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- horse chestnut seed
horse chestnut seed increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- ibuprofen
ibuprofen increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- ibuprofen IV
ibuprofen IV increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- indomethacin
indomethacin increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- ketoprofen
ketoprofen increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- ketorolac
ketorolac increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- ketorolac intranasal
ketorolac intranasal increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .
- mefenamic acid
mefenamic acid increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- meloxicam
meloxicam increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- mistletoe
mistletoe and vitamin K1 (phytonadione) both decrease anticoagulation. Use Caution/Monitor.
- nabumetone
nabumetone increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- naproxen
naproxen increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- nettle
nettle and vitamin K1 (phytonadione) both decrease anticoagulation. Use Caution/Monitor.
- oxaprozin
oxaprozin increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- panax ginseng
panax ginseng increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- pau d'arco
pau d'arco increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- phytoestrogens
phytoestrogens increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- piroxicam
piroxicam increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- reishi
reishi increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- salicylates (non-asa)
salicylates (non-asa) increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- salsalate
salsalate increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- Siberian ginseng
Siberian ginseng increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- sulfasalazine
sulfasalazine increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- sulindac
sulindac increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- tolmetin
tolmetin increases and vitamin K1 (phytonadione) decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- warfarin
vitamin K1 (phytonadione), warfarin. Either decreases effects of the other by anticoagulation. Use Caution/Monitor. Monitor INR with corresponding increases or decreases in vitamin K intake significantly affecting vitamin k blood levels.
Minor (8)
- chlorhexidine oral
chlorhexidine oral will decrease the level or effect of vitamin K1 (phytonadione) by altering intestinal flora. Applies only to oral form of both agents. Minor/Significance Unknown.
- cholestyramine
cholestyramine decreases levels of vitamin K1 (phytonadione) by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown. (Vitamin K).
- ciprofloxacin
ciprofloxacin will decrease the level or effect of vitamin K1 (phytonadione) by altering intestinal flora. Applies only to oral form of both agents. Minor/Significance Unknown.
- colesevelam
colesevelam decreases levels of vitamin K1 (phytonadione) by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown. (Vitamin K).
- colestipol
colestipol decreases levels of vitamin K1 (phytonadione) by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown. (Vitamin K).
- meropenem/vaborbactam
meropenem/vaborbactam will decrease the level or effect of vitamin K1 (phytonadione) by altering intestinal flora. Applies only to oral form of both agents. Minor/Significance Unknown.
- mineral oil
mineral oil decreases levels of vitamin K1 (phytonadione) by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
- orlistat
orlistat decreases levels of vitamin K1 (phytonadione) by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown. Separate by 2 hours.
Adverse Effects
Frequency Not Defined
Anaphylaxis with too-rapid IV administration (has resulted in death)
Dyspnea
Cyanosis
Erythematous skin eruptions
Pruritus
Scleroderma-like lesions
Flushing
Hyperbilirubinemia (in premature neonates)
Hypotension
Injection site reactions
Taste alterations
Postmarketing Reports
Cardiac disorders: Tachycardia
Neurologic: Dysgeusia, dizziness
Skin and subcutaneous tissue disorders: Erythema, pruritic plaques
Warnings
Black Box Warnings
Severe reactions, including fatalities, have occurred during and immediately after IV administration, even when precautions have been taken with proper dilution and avoidance of rapid infusion
Severe reactions also reported after IM administration; typically, these severe reactions involve hypersensitivity or anaphylaxis and include shock and cardiac or respiratory arrest
IV/IM reactions may occur with first dose (no prior exposure to phytonadione)
Restrict use of IV/IM routes to situations where SC administration is not feasible and serious risk involved is considered justified
Contraindications
Hypersensitivity
Cautions
Rapid IV administration may cause potentially fatal anaphylaxis
Protect from light; agent is rapidly degraded
Avoid IM route if patients is bleeding or in 3rd trimester of pregnancy
Administer phtonadione to quickly lower INR into safe range in patients receiving vitamin K antagonists
Other forms of vitamin K (eg, menadione) are not effective in these settings; only vitamin K1 (ie, phytonadione) should be used
Time of onset depends on rate of synthesis of clotting factors
Potential for overcorrection
If initial doses do not reverse coagulopathy, higher doses are not likely to have any effect; inefective in hereditary hypoprothrombinemia
Longer treatment durations (up to months) and much higher doses required in patients exposed to long-acting anticoagulant rodenticide
Hemolysis, hyperbilirubinemia, and jaundice reported in newborns treated with larger than recommended doses; use caution
Parenteral administration may cause cutaneous reactions; reactions have included eczematous reactions, scleroderma-like patches, urticaria, and delayed-type hypersensitivity reactions; time of onset ranged from 1 day to a year after parenteral administration; discontinue therapy for skin reactions and institute medical management
Serious adverse reactions including fatal reactions and “gasping syndrome” reported in premature neonates and infants in the intensive care unit who received drugs containing benzyl alcohol as a preservative; preterm, low-birth weight infants may be more likely to develop these reactions because they may be less able to metabolize benzyl alcohol; preterm, low-birth weight infants may be more likely to develop these reactions because they may be less able to metabolize benzyl alcohol; use benzyl alcohol-free formulations in neonates and infants, if available
Drug interaction overview
-
Anticoagulants
- Mephyton may induce temporary resistance to prothrombin-depressing anticoagulants, especially when larger doses of the drug are used; should this occur, higher doses of anticoagulant therapy may be needed when resuming anticoagulant therapy, or a change in therapy to a different class of anticoagulant may be necessary (ie, heparin sodium)
- The drug does not affect anticoagulant actions of heparin
Pregnancy & Lactation
Pregnancy
The drug formulation contains benzyl alcohol, which has been associated with gasping syndrome in neonates; the preservative benzyl alcohol can cause serious adverse events and death when administered intravenously to neonates and infants; if therapy is needed during pregnancy, consider using a benzyl alcohol-free formulation; published studies with the use of phytonadione during pregnancy have not reported a clear association with phytonadione and adverse developmental outcomes; there are maternal and fetal risks associated with vitamin K deficiency during pregnancy; animal reproduction studies have not been conducted with phytonadione
Pregnant women with vitamin K deficiency hypoprothrombinemia may be at an increased risk for bleeding diatheses during pregnancy and hemorrhagic events at delivery; subclinical maternal vitamin K deficiency during pregnancy has been implicated in rare cases of fetal intracranial hemorrhage
Lactation
The drug formulation contains benzyl alcohol; if available, a Preservative-Free formulation is recommended when therapy is needed during lactation; phytonadione is present in breastmilk; there are no data on effects of therapy on the breastfed child or on milk production; the developmental and health benefits of breastfeeding should be considered along with the clinical need for therapy and any potential adverse effects on breastfed child from the drug or from the underlying maternal condition
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Promotes hepatic synthesis of clotting factors II, VII, IX, X (exact mechanism is unknown)
Pharmacokinetics
Onset: 6-10 hr (PO); 1-2 hr (IV)
Peak effect: 24-48 hr (PO); 12-14 hr (IV)
Metabolism
Metabolized in liver
Elimination
Excretion: Urine, feces
Administration
IV Administration
Dilute in preservative-free NS, D5W, or D5NS and infuse slowly; infusion rate not to exceed 1 mg/min
IV route should be used only if administration by another route is not feasible
Storage
Protect injection emulsion from light at all times
May be autoclaved
Images
BRAND | FORM. | UNIT PRICE | PILL IMAGE |
---|---|---|---|
vitamin K injection - | 1 mg/0.5 mL solution | ![]() | |
Mephyton oral - | 5 mg tablet | ![]() | |
Mephyton oral - | 5 mg tablet | ![]() | |
phytonadione (vitamin K1) oral - | 5 mg tablet | ![]() | |
phytonadione (vitamin K1) oral - | 5 mg tablet | ![]() | |
phytonadione (vitamin K1) oral - | 5 mg tablet | ![]() | |
phytonadione (vitamin K1) oral - | 100 mcg tablet | ![]() | |
Vitamin K1 injection - | 10 mg/mL solution | ![]() | |
phytonadione (vitamin K1) injection - | 1 mg/0.5 mL solution | ![]() |
Copyright © 2010 First DataBank, Inc.
Patient Handout
phytonadione (vitamin K1) oral
VITAMIN K - ORAL
(VYE-ta-min)
COMMON BRAND NAME(S): Mephyton
USES: Vitamin K is used to treat and prevent low levels of certain substances (blood clotting factors) that your body naturally produces. These substances help your blood to thicken and stop bleeding normally (such as after an accidental cut or injury). Low levels of blood clotting factors increase the risk for unusual bleeding. Low levels may be caused by certain medications (such as warfarin) or medical conditions (such as obstructive jaundice). Vitamin K helps to treat and prevent unusual bleeding by increasing the body's production of blood clotting factors.
HOW TO USE: If you are taking the over-the-counter product to self-treat, read all directions on the product package before taking this medication. If you have any questions, consult your pharmacist. If your doctor has prescribed this medication, take it as directed.If you are using the rapidly-dissolving tablets, place under your tongue to dissolve, then swallow with or without water. Some brands may also be swallowed whole.The dosage is based on your age, medical condition and response to treatment. Do not increase your dose or use this drug more often or for longer than directed. Your condition will not improve any faster, and your risk of side effects will increase.If you are using a certain "blood thinner" drug (warfarin), vitamin K can decrease the effects of warfarin for up to 2 weeks. Be sure to take your vitamin K and warfarin exactly as directed by your doctor or pharmacist.If you develop easy bruising or bleeding, or if you think you may have a serious medical problem, get medical help right away. You may need another dose of vitamin K.
SIDE EFFECTS: Vitamin K usually has no side effects. If you have any unusual effects, contact your doctor or pharmacist promptly.If your doctor has directed you to use this product, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this product do not have serious side effects.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Before taking vitamin K, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: blood disorders, gallbladder disease (such as obstructive jaundice, biliary fistula), liver disease.Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).During pregnancy, this product should be used only when clearly needed. Discuss the risks and benefits with your doctor.Vitamin K passes into breast milk, but is unlikely to harm a nursing infant. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.Some products that may interact with this drug include: "blood thinners" (such as acenocoumarol, warfarin).Avoid taking this medication at the same time as orlistat (a weight-management drug). Wait at least 2 hours between taking this medication and orlistat because taking them together may decrease the effect of vitamin K.
OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
NOTES: Lab tests (such as prothrombin time, INR) may be done while you are taking this product. Keep all medical and lab appointments. Consult your doctor for more details.Remember that it is best to get your vitamins and minerals from food whenever possible. Eat a well-balanced diet, and follow any dietary guidelines as directed by your doctor. Foods rich in vitamin K include green leafy vegetables such as spinach, collards, and broccoli.
MISSED DOSE: If you are taking this product on a regular schedule and miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised August 2021. Copyright(c) 2023 First Databank, Inc.
IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
Formulary
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