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Phytonadione oral

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.


COMMON BRAND NAME(S): Mephyton, Vitamin K


Vitamin K is a fat soluble vitamin which plays an important role in blood clotting. This medication is used to prevent and treat hypoprothrombinemia (low blood clot factor levels) caused by vitamin K deficiency.

How To Use

Take this medication by mouth as directed. Do not increase your dose, take this more often or stop taking this without first consulting your doctor or pharmacist. If you are using "blood thinners" (e.g., warfarin): depending on your dosage of vitamin K, it can reverse the effects of warfarin for up to two weeks, which may be undesirable. Therefore, be sure to take your vitamin K and "blood thinners" exactly as directed. If you develop easy bruising or bleeding, seek immediate medical attention. You may require additional vitamin K.

Side Effects

This medication is generally well tolerated. If you notice any unusual effects, contact your doctor or pharmacist.


Tell your doctor if you have: blood disorders, any allergies. This medication should be used as directed during pregnancy or while breast-feeding. Consult your doctor about the risks and benefits.

Drug Interactions

Tell your doctor of any prescription or nonprescription medication you may take, especially of: "blood thinners" (e.g., warfarin), aspirin, NSAIDs (e.g., ibuprofen, naproxen). Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately.


Vitamin K is commonly found in leafy green vegetables, meat, milk, egg yolks and tomatoes. Follow any dietary guidelines recommended by your healthcare professional.

Missed Dose

If you miss a dose, take it as soon as remembered; do not take it if it is near the time for the next dose, instead, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up.


Store at room temperature between 59 and 86 degrees F (15 to 30 degrees C) away from heat and light. Do not store in the bathroom.

Medical Alert

Your condition can cause complications in a medical emergency. For enrollment information call MedicAlert at 1-800-854-1166 (USA), or 1-800-668-1507 (Canada).