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Warfarin

What is Warfarin

Warfarin is an anticoagulant (blood thinner).

Warfarin reduces the formation of blood clots, which is important in the prevention of heart attacks, strokes, and blockage of major veins and arteries.

Warfarin may also be used for purposes other than those listed in this medication guide.

General medical information about Warfarin

Never take a double dose of this medication.

Do not take aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Motrin, Advil, Nuprin, others), ketoprofen (Orudis, Orudis KT, Oruvail), naproxen (Naprosyn, Aleve, Anaprox), and others while taking Warfarin, except under the direction of your doctor. These medicines increase the risk of bleeding.

Avoid sudden changes in your diet. Vitamin K decreases the effects of Warfarin. Large amounts of vitamin K are found in foods such as liver, broccoli, brussels sprouts, and green leafy vegetables (e.g., spinach, Swiss chard, coriander, collards, cabbage). Do not change the amount of these foods in your diet without first talking to your doctor.

It will be necessary to regularly monitor your therapy with a blood test called a "PT" or an "INR." These tests help to determine the amount of Warfarin that you need to take.

Contact your doctor if you experience any unusual bruises or heavily bleeding wounds, diarrhea, infection, or fever during treatment with Warfarin.

What you should find out before taking Warfarin

Do not take Warfarin if you:
- recently had surgery;
- have a stomach ulcer or bleeding in the stomach;
- have had a certain type of stroke caused by bleeding in the brain;
- have had an aneurysm;
- recently had a spinal puncture or lumbar block anesthesia; or
- have bacterial endocarditis (infection of the heart), pericarditis (swelling of tissue around the heart), or pericardial effusion (build-up of fluid around the heart).

Before taking Warfarin, tell your doctor if you:
- have kidney disease;
- have liver disease;
- have high blood pressure;
- have a hereditary protein C or protein S deficiency;
- are diabetic;
- have polycythemia vera;
- have vasculitis;
- have congestive heart failure;
- have a collagen vascular disorder such as systemic lupus erythematosus;
- have thyroid disease;
- have high cholesterol;
- have cancer;
- have a vitamin K deficiency;
- are considering having surgery; or
- are taking antibiotics to treat an infection.

You may not be able to take Warfarin, or you may need a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.

Warfarin is in the FDA pregnancy category X. This means that Warfarin is known to cause birth defects in an unborn baby and must not be taken during pregnancy. Do not take Warfarin if you are pregnant or could become pregnant during treatment. Consult your doctor immediately if you become pregnant while taking Warfarin.

Warfarin has not been detected in human breast milk. Talk to your doctor before taking Warfarin if you are breast-feeding a baby.

How should take Warfarin

Take Warfarin exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.

Take each dose with a full glass of water.

It is important to take Warfarin at the same time every day. Warfarin can be taken with or without food.

It is important to take Warfarin regularly to get the most benefit.

Never take a double dose of this medication.

Do not stop taking Warfarin without first talking to your doctor.

It will be necessary to regularly monitor your therapy with a blood test called a "PT" or an "INR." These tests help to determine the amount of Warfarin that you need to take. Your doctor may also want you to have other blood tests or medical evaluations during treatment with Warfarin to monitor progress and side effects.

Do not take any more or less of this drug than is prescribed for you.

Avoid sudden changes in your diet. Vitamin K decreases the effects of Warfarin. Large amounts of vitamin K are found in foods such as liver, broccoli, brussels sprouts, and green leafy vegetables (e.g., spinach, Swiss chard, coriander, collards, cabbage). Do not change the amount of these foods in your diet without first talking to your doctor.

Contact your doctor if you experience any unusual bruises or heavily bleeding wounds, diarrhea, infection, or fever during treatment with Warfarin.

Store this medication at room temperature away from moisture and heat.

If you miss a dose:

Take the missed dose as soon as you remember, on the same day. If the missed dose is not remembered until the next day, skip that dose and take only the next regularly scheduled dose.Never take a double dose of this medication.

What happens if you overdose:

Seek emergency medical treatment.

Symptoms of a Warfarin overdose include bruising; small, broken blood vessels under the skin; excessive bleeding from cuts or wounds; bleeding from the gums; blood in the stools, urine, or vomit; and excessive menstrual bleeding in women.

Avoid while taking Warfarin

Avoid sudden changes in your diet. Vitamin K decreases the effects of Warfarin. Large amounts of vitamin K are found in foods such as liver, broccoli, brussels sprouts, and green leafy vegetables (e.g., spinach, Swiss chard, coriander, collards, cabbage). Do not change the amount of these foods in your diet without first talking to your doctor.

Do not take aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Motrin, Advil, Nuprin, others), ketoprofen (Orudis, Orudis KT, Oruvail), naproxen (Naprosyn, Aleve, Anaprox) and others while taking Warfarin, except under the direction of your doctor. These medicines increase the risk of bleeding.

Tell your doctor (or dentist) that you are taking Warfarin before taking an antibiotic or before having surgery.

Do not start or stop taking any other medications during treatment with Warfarin without first talking to your doctor.

Avoid hazardous activities and sports that may cause injuries. Bleeding and bruising may be a problem, especially at the start of therapy. Watch for excessive bleeding and bruising and report any unusual bruises or heavily bleeding wounds to your doctor.

Avoid the use of alcohol and tobacco products. These products can alter the effects of Warfarin and cause problems with your therapy. Discuss the use of alcohol and tobacco with your doctor.

Possible side effects of Warfarin

If you experience any of the following serious side effects from Warfarin, stop taking the medication and seek emergency medical attention or contact your doctor immediately:
- an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives);
- black, bloody, or tarry stools;
- blood in urine or vomit;
- coughing up blood;
- bleeding gums or sores in the mouth;
- decreased urine production;
- yellowing of the skin or eyes;
- severe dizziness or headache;
- easy bleeding or bruising under the skin;
- purple discoloration of the toes or fingers;
- sudden leg or foot pain; or
- unusually heavy menstrual periods.

Other, less serious side effects may be more likely to occur. Talk to your doctor if you experience
- excessive gas or bloating;
- diarrhea, nausea, or vomiting;
- hair loss; or
- decreased appetite or weight.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

What other drugs will affect Warfarin

Warfarin interacts with many other drugs, and these interactions can be dangerous, even fatal. Before starting treatment with Warfarin, tell your doctor and pharmacist about all medicines you take including prescription medicines, over-the-counter products, vitamins, minerals, and herbal products. Talk to your doctor and pharmacist before taking any other medication during treatment with Warfarin.

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A
abilify accupril accutane acetaminophen aciphex actifed actonel actos acyclovir adalat adderall adipex advair advil albuterol alesse aleve allegra allopurinol amaryl ambien amiodarone amitriptyline amoxicillin amoxil amphetamine anacin aprazolam aricept asacol aspirin atenolol ativan atorvastatin atrovent augmentin avandia avapro avastin avelox azmacort
B
baclofen
bactrim bactroban baycol benadryl bextra biaxin boniva bontril buspar buspirone
C
caduet campral camptosar capoten captopril cardizem cardura carisoprodol casodex catapress cefzil celebrex celexa cellcept cephalexin cialis cipro ciprodex clarinex claritin climara clindamycin clonazepam clonidine codeine codeprex combivent combivir concerta copaxone coreg coricidin cotrim coumadin cozaar crestor cubicin cyclobenzaprine cymbalta
D
darvocet demerol depakote desogen detrol dextromethorphan diazepam diclofenac didrex diflucan digoxin dilantin diltiazem dimetapp diovan diprivan ditropan doxazosin doxycycline drixoral duragesic dyazide
E
effexor elavil elocon eloxatin emend enalapril enbrel endocet engerix-b entex epogen epzicom erbitux ertaczo ery-tab erythromycin estradiol evista 
F
fabrazyme famotidine fazaclo fenofibrate fioricet fiorinal flexeril flomax flonase flovent fluoxetine fosamax fosrenol furosemide  
G
gabapentin gamimune gemfibrozil gemzar glipizide glucophage glucotrol glucovance glyburide glyburide guaifenesin guaifenex 
H
herceptin humalog humira hydroxyzine hyzaar  
I
ibuprofen imdur imitrex imodium inderal insulin integrilin iressa 
K
kaletra keflex kenalog keppra ketek klonopin kytril  
L
lamictal lamisil lanoxin lantus lasix lescol levaquin levitra levothyroxine levoxyl lexapro lidoderm lipitor lisinopril lithium lorazepam lortab lotensin lotrel lotrisone lovenox lupron luveris  
M
macrobid magnevist meclizine medroxyprogesterone meridia metformin methadone methamphetamine methotrexate methylphenidate methylprednisolone metoclopramide metoprolol metronidazole miacalcin minocycline mobic monopril morphine motrin myfortic  
N
naproxen nasacort nasonex natrecor neulasta neupogen neurontin nexium nifedipine nitrofurantoin norco nortriptyline norvasc  
O
omeprazole omnicef orthovisc oxybutynin oxycodone oxycontin oxytrol  
P
paraplatin patanol paxil pegasys penicillin pepcid percocet percodan percogesic phendimetrazine phenergan phentermine phenytoin plavix plendil potassium pravachol prednisone premarin prempro prevacid prilosec prinivil procrit promethazine propecia propofol propoxyphene propranolol protonix proventil provigil prozac pseudoephedrine pulmicort  
R
ranitidine rebetol reglan relafen relpax remeron remicade renagel renova rhinocort riomet risperdal risperidone ritalin rituxan rocephin rogaine roxicet  
S
sanctura seasonale sensipar serevent seroquel serzone singulair skelaxin soma somavert sonata spiriva spironolactone strattera striant sustiva synagis synthroid 
T
tamoxifen tavist taxol taxotere tegretol temazepam tenormin tenuate tequin terazosin tetracycline tiazac tindamax titralac tobradex topamax toprol tramadol trazodone triamcinolone triaminic triamterene tricor trileptal trimox triphasil trizivir truvada tylenol 
U
ultane ultracet ultram uroxatral
V
valium valtrex vaniqa vasotec velcade verapamil viagra vicodin vicoprofen vidaza viracept viread vytorin  
W
warfarin wellbutrin  
X
xalatan xanax xenical xifaxan xolair xopenex xyrem  
Y
yasmin 
Z
zanaflex zantac zavesca zelnorm zemplar zerit zestoretic zestril zetia ziac zithromax zocor zofran zoladex zoloft zometa zorbtive zosyn zovirax zyrtec zyvox