Medication: Coumadin (warfarin)
Action: Interferes with hepatic synthesis of vitamin
Classification: Anticoagulant
K-dependent clotting factors (II, VII, IX, and X.
Therapeutic Effects: Prevention of
thromboembolic events.
Pharmacokinetics:
Contraindications/Precautions:
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Absorption: absorbed from GI tract after oral
administration.
Distribution: Crosses the placenta but does not
enter breast milk.
Protein Binding; 99%
Metabolism and Excretion: Metabolized by the
liver.
Adverse Reactions/Side Effects:
 Derm: Dermal necrosis, GI: cramps, nausea.
GU: Calciphylaxis. Hemat: Bleeding. Misc.
fever
Drug Interaction: Androgens, capecitabine,
cefotetan, chloramphenicol, clopidogrel, disulfiram,
fluconazole, fluoroquinolones, itraconzole,
metronidazole, thrombolytics, eptifibatide, tirofiban,
sulfonamides, quinidine, quinine, NSAIDs,
Routes/Dosage: PO: (Adults) 2-5mg/day for 2-4
days then adjust daily dose by results of INR.
PO: (Children) Initial loading dose -0.2mg/kg
Assessment: Assess for s/s of bleeding and
hemorrhaging (bleeding gums; nosebleeds; unusual
bruising; tarry black stool.)
Contraindicated in: Uncontrolled bleeding; Open
wounds; Active ulcer disease. Recent brain, eye, or
spinal cord injury.
Use cautiously in: Malignancy; pt. with history of
ulcer, liver disease, or acute kidney injury; History of
poor compliance;
Drug interaction: valporates and aspirin may ^ the
response to warfarin and ^ the risk of bleeding.
Chronic use of acetaminophen may increase risk of
bleeding. Alcohol may decrease action of warfarin.
Ingestion of large qualities of foods high in vitamin K
may antagonize the anticoagulant effect of warfarin.
Drug natural Products: St. John wort decrease
effect. ^bleeding risk with anise, arnica, chamolie,
clove, dong quai, garlic ginger, ginko .
Assessment: Assess for increased in thrombosis.
Monitor PT/INR and other clotting factors frequent
during therapy. Therapeutic range: 1.3-1.5 times.
Monitor stool and urine for occult blood before and
periodically during therapy.
Potential Nursing Diagnoses:
Implementation: Do not confuse Coumadin
Ineffective tissue perfusion (indications)
Risk for Injury (side effects)
Patient/Family Teaching: Instruct Patient to take
medication as directed. Take miss dose as soon as
remember that day; do not double dose. Inform health
care professional of missed dose. Review Foods high in
Vitamin K. Pt should have consisted limited intake of
these foods as Vitamin K is the antidote for Warfarin.
(warfarin) with Avandia(rosiglitazone) or Cardura
(doxazosin). Do not confused Jantoven (warfarin)
with Janumet or Januvia.
Because of the large number of medications
capable of significantly altering warfarin effects,
careful monitoring is recommended when new agents
are started, or other agents are discontinued.
Interactive potential should be evaluated for all new
medications (Rx, OTC, and herbal products).
Patient/family Teaching: Advise pt. to avoid
Evaluation/Desired Outcomes:
cranberry juice or products during therapy. Advise pt. to
report any symptoms of unusual bleeding or bruising
and pain, color, temp. change to any area of the body to
health care professional.
Prolonged PT (1.3-2.0 times the control; may vary
with indication or INR of 2-4.5 without signs of
hemorrhage.