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Through Thick and Thin
Learning to Live with Warfarin
South Denver Cardiology Associates PC
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What is Anticoagulation?
- Anti = against
- Coagulation = blood clotting
- An anticoagulant is a medication that
reduces the bloods potential to clot
- Anticoagulants are often called
“blood-thinners”
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Reasons for Anticoagulation Therapy
- Deep Vein Thrombosis (DVT)
- Mechanical Heart Valve Replacement
- Pulmonary Embolus (PE)
- Atrial Fibrillation (Afib)
- Atrial Flutter (Aflutter)
- Myocardial Infarction (MI) or Heart Attack
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Reasons for Anticoagulation Therapy
- Cardiomyopathy or Left Ventricular
Dysfunction
- Stroke
- Transient Ischemic Attack (TIA)
- Post-operative
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About Warfarin (Coumadin®)
- Warfarin therapy monitored by blood test
called INR (International Normalized Ratio)
- MD will prescribe what range INR needs to be
- INR = 0.9-1.1, without warfarin
- INR =2.0-3.0, for most indications
- INR = 2.5-3.5, for mechanical heart valves and other conditions
- general guidelines, may have different range according to medical condition or other risk factors
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About Warfarin (Coumadin®)
- Warfarin has a “narrow therapeutic range”
- When INR falls within prescribed range,
level is “therapeutic”
- When INR falls below prescribed range:
- INR = 1.5, for example
- blood is “too thick”, clotting too fast
- risk for forming blood clots exists
- warfarin dose needs to be increased
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About Warfarin (Coumadin®)
- When INR is above prescribed range:
- INR = 4.5, for example
- blood is “too thin”, clotting too slowly
- higher risk for bleeding
- warfarin dose needs to be decreased
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About Warfarin (Coumadin®)
- The dose of warfarin needed is the one that
will keep INR in therapeutic range
- some people need very large dose of warfarin
- some people need very small dose of warfarin
- The dose of warfarin will fluctuate with
changing INR values
- dose likely to change with each INR in first month of therapy
- will change after first month with changes in diet, medications, activity and overall health
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About Warfarin (Coumadin®)
- When a stable dose of warfarin has been
found
- INR needs to be checked once a month
- If INR is stable for several consecutive months a 6-week schedule may be considered for INR’s
- It is very important to call for earlier INR
appointment if there are changes
- in diet, medications, activity and overall health
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About Warfarin (Coumadin®)
- If a dose of warfarin is missed it can be
taken later the same day
- If previous days’ dose was missed
- DO NOT TAKE A DOUBLE DOSE!
- Get back on dosing schedule and let healthcare provider know the date of the missed dose with next INR
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About Warfarin (Coumadin®)
- If more than 1 or 2 doses are missed
- call healthcare provider to discuss
- INR may need to be checked
- You are not likely to have symptoms if INR
is too low or too high
- This is why regular testing of INR is so
important
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Warfarin and Side Effects
- The most common and serious side effect of
warfarin therapy is bleeding
- The risk of bleeding is relatively small when warfarin is taken properly
- To lower the risk, make sure to have INR levels checked regularly
- Report any changes in diet, medications, activity and overall health
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Warfarin and Side Effects
- Any of these symptoms could be
significant, but may not be dangerous
- In therapeutic doses warfarin does not cause
bleeding, but will make it harder to stop
bleeding if an injury occurs
- Primary care physician (PCP) will need to
be aware of, and treat any of these side
effects
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Warfarin and Side Effects
- For minor bleeding
- nosebleed or bleeding gums that stop within a few minutes
- Call healthcare provider so INR can be
checked
- Reporting bleeding symptoms early and
having warfarin dose adjusted
- can prevent INR from increasing and more serious side effects from occurring
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Warfarin and Side Effects
- GET TO THE NEAREST EMERGENCY
ROOM
- If you have major bleeding
- Nosebleed that does not stop after 15-20 minutes
- Frank blood in stools, or black, tarry stools
- Vomiting bright red or coffee-ground emesis
- If you sustain a traumatic injury from a fall or car accident - You will need to be checked for internal bleeding
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Warfarin and Side Effects
- GET TO THE NEAREST EMERGENCY
ROOM
- If you are exhibiting signs of a stroke or “brain attack” - Sudden numbness or weakness of face, arm or leg - Difficulty speaking or understanding others - Problems seeing clearly - Confusion, dizziness, severe drowsiness - Loss of coordination - Sudden severe headache with no known cause
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Special Considerations with Warfarin
- Advisable to wear a Medic-Alert bracelet
- To notify emergency healthcare personnel you are taking anticoagulants
- Have an updated medication list
- In wallet or billfold and with you at all times
- Be careful! Use common sense!
- You are taking a blood thinner and are going to bruise more easily and bleed longer than before you took warfarin
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Warfarin and Drug Interactions
- Warfarin has hundreds of drug interactions
- With prescription, over-the-counter and herbal medicines
- Not all medications affect everyone the same
- Initiation of some meds warrant an INR within 2-3 days
- Initiation or change in others may need INR to be checked within 2 weeks
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Warfarin and Drug Interactions
- One of the most preventable causes of an
untherapeutic INR
- Is to inform healthcare provider when making any medication changes, however minor they may seem
- If you need to take a medication that
interacts with warfarin
- You will need more frequent testing of INR and adjustment in dose until INR is stable
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Warfarin and Diet
- Warfarin works against vitamin K in diet
- Vitamin K is important in forming blood clots
- Foods with the highest amounts of vitamin K are green, leafy vegetables
- Green vegetables are important!
- Contain folic acid, phytonutrients and fiber
- All of which help protect your heart and have countless other benefits to body
- Eat your veggies!
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Warfarin and Dietary Supplements
- Dietary supplements such as Ensure, Boost,
Carnation Instant Breakfast, and various
protein drinks are ‘high’ in vitamin K
- If you start a dietary regimen with any of these
- Be consistent
- Call healthcare provider, as warfarin dose will likely need to be adjusted
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Warfarin and Vitamins
- Multi-vitamins (MVI)
- Contain vitamin K
- Call healthcare provider if starting or changing
- Pay attention to vitamin K content when choosing or switching brands
- Viactiv MVI and Calcium chews have extremely high amounts of vitamin K
- B Vitamins
- Have little to no effect on warfarin
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Warfarin and Vitamins
- Vitamin C
- Up to 500mg daily has no affect, greater than 500mg daily may effect warfarin dosage
- Vitamin E
- Up to 400 iu daily has no affect, doses greater than that may increase INR
- Fish oil
- Likely to increase INR and require dose adjustment
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Warfarin and Alcohol
- Drinking alcohol can affect INR and is not
always predictable
- Best not to drink alcohol, but alcoholic
beverages in moderation can be safe
- One or two drinks each day
- 12 oz. Beer = 4 oz. Wine = 1 oz. Liquor
- It is best to be consistent from week to week
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Warfarin and Medical, Surgical
or Dental Procedures
- Contact your healthcare provider any time
you need to have a procedure that puts you
at risk for bleeding
- Warfarin may need to be temporarily stopped
- It may not be safe for you to stop your anticoagulants entirely - You may need an alternative method of anticoagulation
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Warfarin and Travel
- Travel can often affect INR levels
- Have INR checked before travelling
- If an INR needs to be checked while away,
or you will be gone for an extended time
- Your healthcare provider can help you make arrangements to have it checked while away
- Try to maintain a consistent diet and avoid
excessive alcohol intake
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