Warfarin: profile and news

Airline Cabin Conditions Not Linked to Blood Clots  17 May 2006
People at risk for DVT may be prescribed the blood thinner Coumadin (warfarin) to keep clots from growing. ... Warfarin interacts with many other medications. ... - Food Consumer,

Safe pesticide alternatives exist  17 May 2006
...that “many of the most commonly used sprays are not only safe, but actually used on humans in medical settings.� He uses the example of warfarin as an anti ... - Tonawanda News,

New options make heart failure a condition to live with  17 May 2006
...brain and cause a stroke. Anticoagulants, such as warfarin (Coumadin), are prescribed to prevent that. Especially in the beginning ... - DetNews.com,

Chamomile plus warfarin: a potentially dangerous mix  May 4, 2006
By Megan Rauscher. NEW YORK (Reuters Health) - People taking warfarin to prevent blood clots should stay away from chamomile products, Canadian doctors caution. ... - Reuters

Chamomile plus warfarin: a dangerous mix  May 5, 2006
People taking warfarin to prevent blood clots should stay away from chamomile products, Canadian doctors caution. They describe ... - Ninemsn,

Oral Direct Thrombin Inhibitor Ximelagatran Compared with Warfarin ...  May 1, 2006
After reading the article by Colwell et al., "Oral Direct Thrombin Inhibitor Ximelagatran Compared with Warfarin for the Prevention of Venous Thromboembolism ... - Journal of Bone and Joint Surgery

Reducing Warfarin Medication Interactions  May 8, 2006
...record, we evaluated the effectiveness of electronic medical record alerts and group academic detailing to reduce the coprescribing of warfarin and interacting ... - Archives of Internal Medicine

Don't mix chamomile tea/warfarin  Apr 27, 2006
...drug. The 70-year-old patient had been implanted with a mechanical valve and had been taking the anticoagulant medication warfarin. ... - United Press International

In acute coronary syndrome, aspirin plus warfarin was superior for ...  Apr 17, 2006
2006 APR 17 - (NewsRx.com) -- For patients recovering from acute coronary syndrome, a combined strategy of aspirin plus warfarin doubles the risk of major ... - Therapeutics Daily (subscription) (press release),

Tm Bioscience reports first quarter 2006 results  May 15, 2006
FDA's Clinical Pharmacology Subcommittee of the Advisory Committee on Pharmaceutical Science voted in November 2005 in favor of changing Warfarin's label to ... - Yahoo! News (press release)

Chamomile plus warfarin: a dangerous mix  May 5, 2006
By Megan Rauscher. People taking warfarin to prevent blood clots should stay away from chamomile products, Canadian doctors caution. ... - Seven.com.au,

Internal Bleeding Risk From Camomile Plus Blood-Thinners  May 9, 2006
...a Canadian woman experienced severe internal haemorrhaging when she drank camomile tea and used camomile lotion while taking the blood-thinning drug warfarin. ... - StaffNurse.com,

Data from Italy, Israel and Norway advance knowledge in cardiology ...  May 15, 2006
Study 1: For patients recovering from acute coronary syndrome, a combined strategy of aspirin plus warfarin doubles the risk of major bleeds, but is superior ... - Therapeutics Daily (subscription) (press release),

Herbs, Prescription Drugs Sometimes Don't Mix  May 10, 2006
Mixing ginseng, garlic or gingko biloba, for example, with common heart medications like Coumadin or blood thinners like Warfarin could lead to uncontrolled ... - NBC 17.com,

Former soldier fired at police in house siege  May 16, 2006
Leeds Crown Court heard yesterday how the 50-year-old had suffered from depression since childhood and was taking Prozac, Warfarin and a number of other anti ... - Yorkshire Post Today,

Fatal pulmonary microthrombi during surgical therapy for end-stage ...  May 15, 2006
...coagulation. In addition, they are commonly receiving both systemic anticoagulation (warfarin or heparin) and antiplatelet therapy. ... - The Journal of Thoracic and Cardiovascular Surgery

New Study Shows Initial Treatment With 800 mg/day Imatinib ...  May 15, 2006
Examples of commonly used drugs that may significantly interact with Gleevec include acetaminophen, warfarin, erythromycin, and phenytoin. ... - DG News

Letter to the Editor  May 1, 2006
...all causes) is valid. There was a significant difference in the efficacy end point between ximelagatran and warfarin. The use of ... - Journal of Bone and Joint Surgery

Pesticide laws increase safety, but hurt business  May 9, 2006
Take warfarin for example. Warfarin is the active chemical in some pesticide sprays, but it also serves another purpose, Burton said. ... - Tonawanda News,

Never Mind Long-Haul Flights, I Got DVT Froma Bout of Flu ...  May 9, 2006
...days. It is likely I will be on warfarin tablets for several months to 'thin my blood' and prevent further blood clots from forming. ... - International News Service,

New method promotes pharmacogenomic benefits  May 9, 2006
...used this mouse genetic analysis method, which utilised a computational method for identifying factors that regulate the metabolism of warfarin, a widely used ... - DrugResearcher.com,

Myriad Genetics Begins Phase 1 Trial of Anti-Thrombin Drug MPC ...  May 2, 2006
The drugs currently used to treat this condition are the anticoagulants heparin and warfarin (tradename Coumadin®). These drugs are widely used. ... - Yahoo! News (press release)

Chamomile Tea And Lotion Causing Internal Bleeding In Patient On ...  May 2, 2006
The patient had been implanted with a mechanical valve and was taking an anti-coagulant medication called warfarin, designed to thin the blood and reduce the ... - Medical News Today (press release),

Severe intracranial stenosis represents a major risk factor for ...  May 5, 2006
The researchers' findings are part of a larger multi-site clinical investigation - specifically, the Warfarin versus Aspirin for Symptomatic Intracranial ... - Xagena.it,

HemoSense Receives StarLine's Rookie of the Year Award  May 11, 2006
HemoSense develops, manufactures and markets easy-to-use, handheld blood coagulation systems for monitoring patients taking warfarin. ... - Business Wire (press release),

Antiplatelets Recommended For Prevention Of Recurrent Stroke Or ...  Apr 22, 2006
Results of the Warfarin-Aspirin Recurrent Stroke Study published in the journal "Cerebrovascular Diseases" show no benefit of warfarin over aspirin for the ... - Medical News Today (press release),

Myriad Genetics: clogging up the anti-thrombin drug race?  May 5, 2006
...the thrombosis treatments market offers great commercial potential, Myriad Genetics is a relatively late entrant in the race to replace warfarin, and thus its ... - Pharmaceutical Business Review

Bosses 'conspired to keep price of nhs drugs high'  May 5, 2006
...together to dishonestly abuse the prevailing system in place as regards the two specified drugs known as the antibiotic family of drugs and the warfarin family ... - ic SouthLondon.co.uk,

Proximal Deep Vein Thrombosis After Hip Replacement for Oncologic ...  May 1, 2006
...similar 13 . Patients who were found to have a deep vein thrombosis were treated with warfarin for six months. Preoperative duplex ... - Journal of Bone and Joint Surgery

Legislators urge DOH to recall inadequately labeled supplement  Apr 17, 2006
...that the product is not for children under 15, or pregnant and nursing women, it fails to clearly note the risk of taking CoQ10 for those on Warfarin, a common ... - eTaiwan News,

Encysive Evasive About Thelin  May 11, 2006
So why was the letter issued? One theory speculates that the FDA had concerns about Thelin's interaction with Warfarin, another common treatment for PAH. ... - Motley Fool

Roche research sheds light on drug metabolism  May 9, 2006
The researchers used a computational method for mouse genetic analysis to identify factors that regulate the metabolism of warfarin, a widely used anticoagulant ... - Pharmaceutical Business Review

Genetic Research Method Sheds Light on Drug Metabolism  May 9, 2006
...of General Medical Sciences, utilized a computational method for mouse genetic analysis to identify factors that regulate the metabolism of warfarin, a widely ... - GenomicsProteomics.com (press release),

Pregnant women are orphaned from the tremendous progress in drug ...  May 10, 2006
Programs: - It took almost four years of marketing before the link between thalidomide and limb defects was recognized - Malformations with warfarin took over ... - Canada NewsWire (press release),

Defective Heart Valves, Pacemakers, and Defibrillators Propose New ...  Apr 20, 2006
These patients must take anticoagulation medicine, like Warfarin (coumadin) to prevent deadly blood clots. Years after their removal from the market, St. ... - PR Web (press release),

HemoSense Reports Fiscal 2006 Second Quarter Revenue up 125% ...  Apr 27, 2006
...easy-to-use, handheld blood coagulation monitoring systems for use by patients and healthcare professionals in the management of warfarin medication -- today ... - Genetic Engineering News,

Extraordinary measures look better once you're ill  Apr 28, 2006
...severe internal bleeding. The woman had a heart condition and had been prescribed warfarin, a blood-thinning medication. Doctors in ... - Globe and Mail,

Lifetime of meds needed for heart out of rhythm  Apr 30, 2006
...your symptoms and situation. Warfarin (Coumadin), a blood-thinning medication, helps reduce the risk of stroke. Most people also ... - Fort Wayne Journal Gazette,

Myriad strong for `06, beyond  May 2, 2006
...candidate has shown promise in 27 preclinical studies and that it may offer benefits over current anti-thrombosis treatments, including heparin and warfarin. ... - Monsters and Critics.com,

Doctors attack leading cause of stroke  May 5, 2006
Medicines include drugs that control heart rhythm or slow rapid heart rate and anticoagulants such as warfarin that reduce the risk of stroke. ... - San Luis Obispo Tribune,

Atrial fibrillation: beyond drug therapies  May 7, 2006
...rhythm. Moreover, the atria continued to fibrillate, so anticlotting medication, usually warfarin (Coumadin), was still needed. ... - ITP.net,

Nine pharmacists on trial for controlling drug prices  May 7, 2006
...and others engaged in the provision of medicinal products by dishonestly fixing and maintaining the price and manipulating the supply of warfarin and marevan ... - This Is Hertfordshire,

Localization in clinical neurology  May 3, 2006
...disease. Aspirin is still widely used for ischaemic stroke, and warfarin in fewer cases—both of which are very old treatments. ... - Journal of the Royal Society of Medicine

CDC Calls for Reproductive Life Plans  Apr 21, 2006
The oral anticoagulant Coumadin. Coumadin (warfarin), which is used for the control of blood clotting, has been demonstrated to be a teratogen. ... - MedPage Today,

Not all guidelines on treating heart failure in adults apply to ...  May 2, 2006
Meta-analyses of the two largest studies of anti-thrombotic therapy have not shown a difference in mortality or vascular events between warfarin and aspirin. ... - AAP News (subscription)

Herbs the tonic for back pain  Apr 19, 2006
Devil's Claw could cause peptic upset in some patients, and White Willow Bark could interact with the blood-thinning drug warfarin. ... - NEWS.com.au,

Dealing with the sunscreen dilemma  Apr 16, 2006
A: Feverfew has the potential to interact with a great many medications, especially blood thinners like Coumadin (warfarin), aspirin or Plavix (clopidogrel). ... - Houston Chronicle,

Drugs may interact with COUMADIN through pharmacodynamic or pharmacokinetic mechanisms. Pharmacodynamic mechanisms for drug interactions with COUMADIN are synergism (impaired hemostasis, reduced clotting factor synthesis), competitive antagonism (vitamin K), and altered physiologic control loop for vitamin K metabolism (hereditary resistance). Pharmacokinetic mechanisms for drug interactions with COUMADIN are mainly enzyme induction, enzyme inhibition, and reduced plasma protein binding. It is important to note that some drugs may interact by more than one mechanism.

The following factors, alone or in combination, may be responsible for INCREASED PT/INR response

ENDOGENOUS FACTORS

EXOGENOUS FACTORS

Potential drug interactions with COUMADIN are listed below by drug class and by specific drugs.

also: other medications affecting blood elements which may modify hemostasis dietary deficiencies prolonged hot weather unreliable PT/INR determinations

^† increased and decreased PT/INR responses have been reported.

The following factors, alone or in combination, may be responsible for DECREASED PT/INR response

ENDOGENOUS FACTORS

EXOGENOUS FACTORS

Potential drug interactions with COUMADIN (Warfarin Sodium) are listed below by drug class and by specific drugs.

also: diet high in vitamin K unreliable PT/INR determinations

^†Increased and decreased PT/INR responses have been reported.

Because a patient may be exposed to a combination of the above factors, the net effect of COUMADIN on PT/INR response may be unpredictable. More frequent PT/INR monitoring is therefore advisable. Medications of unknown interaction with coumarins are best regarded with caution. When these medications are started or stopped, more frequent PT/INR monitoring is advisable.

It has been reported that concomitant administration of warfarin and ticlopidine may be associated with cholestatic hepatitis.

Botanical (Herbal) Medicines

Caution should be exercised when botanical medicines (botanicals) are taken concomitantly with COUMADIN. Few adequate, well-controlled studies exist evaluating the potential for metabolic and/or pharmacologic interactions between botanicals and COUMADIN. Due to a lack of manufacturing standardization with botanical medicinal preparations, the amount of active ingredients may vary. This could further confound the ability to assess potential interactions and effects on anticoagulation. It is good practice to monitor the patient’s response with additional PT/INR determinations when initiating or discontinuing botanicals.

Specific botanicals reported to affect COUMADIN therapy include the following:

• Bromelains, danshen, dong quai (Angelica sinensis), garlic, Ginkgo biloba, and ginseng are associated most often with an INCREASE in the effects of COUMADIN.

• Coenzyme Q₁₀ (ubidecarenone) and St. John’s wort are associated most often with a DECREASE in the effects of COUMADIN.

Some botanicals may cause bleeding events when taken alone (e.g., garlic and Ginkgo biloba) and may have anti-coagulant, antiplatelet, and/or fibrinolytic properties. These effects would be expected to be additive to the anticoagulant effects of COUMADIN. Conversely, other botanicals may have coagulant properties when taken alone or may decrease the effects of COUMADIN.

Some botanicals that may affect coagulation are listed below for reference; however, this list should not be considered all-inclusive. Many botanicals have several common names and scientific names. The most widely recognized common botanical names are listed.

Effect on Other Drugs

Coumarins may also affect the action of other drugs. Hypoglycemic agents (chlorpropamide and tolbutamide) and anticonvulsants (phenytoin and phenobarbital) may accumulate in the body as a result of interference with either their metabolism or excretion.

Special Risk Patients

COUMADIN (Warfarin Sodium) is a narrow therapeutic range (index) drug, and caution should be observed when warfarin sodium is administered to certain patients such as the elderly or debilitated or when administered in any situation or physical condition where added risk of hemorrhage is present.

Intramuscular (I.M.) injections of concomitant medications should be confined to the upper extremities which permits easy access for manual compression, inspections for bleeding and use of pressure bandages.

Caution should be observed when COUMADIN (or warfarin) is administered concomitantly with nonsteroidal antiinflammatory drugs (NSAIDs), including aspirin, to be certain that no change in anticoagulation dosage is required. In addition to specific drug interactions that might affect PT/INR, NSAIDs, including aspirin, can inhibit platelet aggregation, and can cause gastrointestinal bleeding, peptic ulceration and/or perforation.

Acquired or inherited warfarin resistance should be suspected if large daily doses of COUMADIN are required to maintain a patient’s PT/INR within a normal therapeutic range.

SIDE EFFECTS

Potential adverse reactions to COUMADIN may include:

• Fatal or nonfatal hemorrhage from any tissue or organ. This is a consequence of the anticoagulant effect. The signs, symptoms, and severity will vary according to the location and degree or extent of the bleeding. Hemorrhagic complications may present as paralysis; paresthesia; headache, chest, abdomen, joint, muscle or other pain; dizziness; shortness of breath, difficult breathing or swallowing; unexplained swelling; weakness; hypotension; or unexplained shock. Therefore, the possibility of hemorrhage should be considered in evaluating the condition of any anticoagulated patient with complaints which do not indicate an obvious diagnosis. Bleeding during anticoagulant therapy does not always correlate with PT/INR.

• Bleeding which occurs when the PT/INR is within the therapeutic range warrants diagnostic investigation since it may unmask a previously unsuspected lesion, e.g., tumor, ulcer, etc.

• Necrosis of skin and other tissues.

• Adverse reactions reported infrequently include: hypersensitivity/allergic reactions, systemic cholesterol microembolization, purple toes syndrome, hepatitis, cholestatic hepatic injury, jaundice, elevated liver enzymes, vasculitis, edema, fever, rash, dermatitis, including bullous eruptions, urticaria, abdominal pain including cramping, flatulence/bloating, fatigue, lethargy, malaise, asthenia, nausea, vomiting, diarrhea, pain, headache, dizziness, taste perversion, pruritus, alopecia, cold intolerance, and paresthesia including feeling cold and chills.

Rare events of tracheal or tracheobronchial calcification have been reported in association with long-term warfarin therapy. The clinical significance of this event is unknown.

Priapism has been associated with anticoagulant administration, however, a causal relationship has not been established.

 


Chemical IUPAC Name
2-hydroxy-3-(3-oxo-1-phenyl-butyl)-chromen-4-one

Chemical Formula
C19H16O4

Half Life
1 week

Drug Type
Approved Drug

# Accession No
APRD00341

CAS Registry Number
81-81-2