Warfarin Patient Education Flashcards
What is Warfarin?
Warfarin is an anticoagulant, or “blood
thinner,” that prevents and treats harmful
blood clots in veins, arteries, brain, lungs,
and heart.
How does it work?
Warfarin decreases the amount of clotting
factors your body makes by acting against
vitamin K. This prevents clots from forming
or getting bigger.
Why use?
After an injury, your body uses clotting
factors to stop the bleeding. Vitamin K is
needed to make some of the clotting
factors. Sometimes harmful blood clots
can form in the veins of your legs, lungs,
brain, or heart and cause a blockage.
What is it used to treat?
Warfarin is used to prevent or treat blood
clots in patients with:
• Mechanical or bioprosthetic heart valves
• A type of irregular heart beat known as
atrial fibrillation (Afib)
• Recent hip or knee replacement surgery
• Current or high risk of blood clots in the heart (myocardial infarction, MI), brain (stroke), veins (deep vein thrombosis, DVT) or lungs (pulmonary embolism, PE)
Will I need routine blood checks?
You will need your blood tested to check your INR
result. Your INR number tells us if your blood is
“too thin” making it easier to bleed, “too thick”
putting you at risk of a blood clot, or at goal.
You will need to have your blood tested more
often when you start taking warfarin until your INR
is stable in your INR goal range.
How should I take it?
Take your warfarin at the same time every day, if possible in the evening.
Did you miss a dose?
If you miss a dose, take it as soon as you remember on the same day. If you remember the next morning, take your regular dose. Do
not take two doses at once. Call your doctor or anticoagulation clinic if you miss a dose.
How should I store it?
Store at room temperature in a tightly sealed pill
bottle. Keep away from light and humidity.
Do not store in the bathroom.
What are the side effects?
Minor bleeding is the most common side effect of this medication, this includes: • Bruising more easily • Occasional, light nose bleeds • Prolonged and heavier than normal menstrual bleeding • Prolonged bleeding after minor cuts
Call your doctor or seek emergency
help immediately if you notice
- Allergic reaction: itching or hives,swelling in your face, mouth, or throat, or trouble breathing
- Blistering, peeling, or red skin rash
- Bloody or brown urine
- Bloody or black, tarry stools
- Vomit that is bloody or looks likecoffee grounds
Avoid activities that put you at risk of injury or falling. Seek emergency help
if you fall and hit your head.
Are there restrictions on
food or alcohol?
Foods that have vitamin K allow more clotting factors to be made.
While taking
warfarin, your goal should be to eat the same amount of vitamin K each week.
Eating more or less foods with vitamin K can change your response to warfarin.
Limit intake of grapefruit and grapefruit
juice. These may increase risk of bleeding.
Alcohol use can also change the effects of
warfarin. It is recommended to limit alcohol use.
Inform your doctor or anticoagulation
clinic if you drink socially or daily.
Some medications may increase your
chance of bleeding and should be avoided.
Some examples include:
- aspirin
- ibuprofen (Motrin, Advil®)
- naproxen (Naprosyn, Aleve®)
- diclofenac (Voltaren®)
- celecoxib (Celebrex®)
- clopidogrel (Plavix®)
- ticagrelor (Brillinta®)
- enoxaparin (Lovenox®)
There are other medications your doctor
should be aware of that can affect how
warfarin works. Some examples are:
• Antibiotics: clarithromycin (Biaxin®), levofloxacin (Levaquin®), metronidazole
(Flagyl®), trimethoprim-sulfamethoxazole
(Bactrim® or Septra®), doxycycline, etc.
• fluconazole (Diflucan®) • lovastatin (Mevacor®) • rifampin (Rifadin®) • amiodarone (Pacerone®) • carbamazepine (Tegretol®) • phenytoin (Dilantin®) • phenobarbital • Herbal supplements, including: turmeric, fish oils, St. John’s wort, coenzyme Q10
