Warfarin ( Coumadin )

Lifestyle diet and habits

Assess diet for pts diet habits, high vitamin k decreases the effectiveness of warfarin, if diet was normally rich in vitamin k when the warfarin dosage was adjusted restricting these foods is not important many herbal preparations interact with warfarin , assess for their use

Health status

Assess the availability of vitamin k b/c defenciences increase the bleeding risk for pts receiving warfarin they experience decreased synthesis of normal clotting factors

Adverse effects

Bleeding and hemorrhage, nausea, vomiting , diarrhea and abdominal cramps

Life span / gender

Consider pts age before therapy begins . Newborns have a vitamin k deficiency b/c intestinal flora is not active at birth, bleeding complications with anticoagulant drugs occur more in the elderly. Assess for pregnant pts this drug should not. Be used during pregnancy it's a category X it causes fetal defects

C/P

Contraindicated for pts with active bleeding , open wounds or ulcerations of the GI tract or bleeding disorders such as hemophilia or thrombocytopenia It's not recommended for use in pts with subacute endocarditis, pericarditis or pericardial effusions . This drug is Also contraindicated with pts undergoing surgery while hemorrhage is possible , drug is usually discontinued 7 days before surgery Caution in pts with renal and hepatic impairment

Minizuming A.E

Monitor for signs if bleeding , the antidote for warfarin overdose is vitamin k and falls may cause internal bleeding . Encourage the use of proper lighting and hand rails on stairways which may help prevent falls

Maximizing T.E

Monitor pt for therapuetic range adjust dosage until therapuetic range is attained

Pt teaching

Teach pt signs of bleeding and methods to prevent bleeding Take drug at the same time each day After the drug level is stabilized and daily pt is not needed , may switch to morning dosing Advise pts to return follow up blood work Skipping a dose of warfarin could alter therapuetic level If pt forget a dose they should take as soon as they remember but don't double dose Instruct pts that taking aspirin, large doses of Tylenol or other OTC drugs with this ingredients can affect warfarin action Warn women to avoid becoming pregnant while taking this drug Dietary teaching focus on avoiding foods rich in vitamin k ( green vegetables ) Emphasize the importance of informing other health care providers like dentist and podiatrist

Pharmacotherapuetics

Warfarin (Coumadin) is an oral anticoagulant . It is adminstered after heparin therapy for 3 to 6 months to complete treating a thrombus or embolism. This drug is used prophylacticallly for pts with long term risk for thrombus formation Starting dose should be 5 to 10 mg for the 1st to 2nd day then adjust by clinical response being achieved

Pharmacokinetics

Warfarin is bound to albumin after absorption it crosses the placenta but not. Found in breast milk Met liver , Exc bile

Environment

Warfarin therapy may be started in the hospital but most treatment is self adminstered at home Explore the potential risks in the home

Pharmacodynamics

Works by competitively blocking vitamin k at its site of action , it prevents the activation of factors II, VII, IX and X(prothrombin)