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 (e.g., 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 (e.g., warfarin) or medical conditions (e.g., obstructive jaundice). Vitamin K helps to treat and prevent unusual bleeding by increasing the body's production of blood clotting factors.
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.
Take this medication by mouth exactly as directed by your doctor. Dosage is based on your medical condition and response to treatment.
If you are using a certain "blood thinner" drug (warfarin), vitamin K can decrease the effects of warfarin for up to 2 weeks. Therefore, be sure to take your vitamin K and warfarin exactly as directed by your doctor or pharmacist.
If you develop easy bruising or bleeding, seek immediate medical attention. You may need another dose of vitamin K.
Vitamin K usually has very few side effects. If you have any unusual effects from taking this medicine, tell your doctor or pharmacist promptly.
If your doctor has prescribed this medication, remember that he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention 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, tell your doctor or pharmacist.
In the US -
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.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.
Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: "blood thinners" (e.g., warfarin), nonsteroidal anti-inflammatory drugs-NSAIDs (e.g., ibuprofen, naproxen).
Aspirin can increase the risk of bleeding. However, if your doctor has directed you to take low-dose aspirin for heart attack or stroke prevention (usually at dosages of 81-325 milligrams a day), you should continue taking it unless your doctor instructs you otherwise. Ask your doctor or pharmacist for more details.
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.
This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
Do not share this medication with others.
Laboratory and/or medical tests (e.g., prothrombin time, INR) should be performed to monitor your progress or check for side effects. Consult your doctor for more details.
Vitamin K is commonly found in leafy green vegetables such as spinach, collards, and broccoli. Follow any dietary guidelines recommended by your health care professional.
If you are taking this product on a prescribed 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 and resume your usual dosing schedule. Do not double the dose to catch up.
Store at room temperature between 59-86 degrees F (15-30 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines away from children and pets.
Information last revised December 2013. Copyright(c) 2013 First Databank, Inc.
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