Tìm theo
Heparin
Các tên gọi khác (7 ) :
  • Calciparine
  • Eparina
  • Hep-lock
  • Heparinate
  • Heparinic acid
  • Liquaemin
  • Panheprin
Thuốc tác dụng đối với máu
Thuốc Gốc
Small Molecule
CAS: 9005-49-6
ATC: C05BA01, C05BA03, S01XA09, S01XA14
ĐG : Amerisource Health Services Corp. , http://www.amerisourcebergen.com
Unfractionated heparin (UH) is a heterogenous preparation of anionic, sulfated glycosaminoglycan polymers with weights ranging from 3000 to 30,000 Da. It is a naturally occurring anticoagulant released from mast cells. It binds reversibly to antithrombin III (ATIII) and greatly accelerates the rate at which ATIII inactivates coagulation enzymes thrombin (factor IIa) and factor Xa. UH is different from low molecular weight heparin (LMWH) in the following ways: the average molecular weight of LMWH is about 4.5 kDa whereas it is 15 kDa for UH; UH requires continuous infusions; activated partial prothrombin time (aPTT) monitoring is required when using UH; and UH has a higher risk of bleeding and higher risk of osteoporosis in long term use. Unfractionated heparin is more specific than LMWH for thrombin. Furthermore, the effects of UH can typically be reversed by using protamine sulfate.
Nhận Dạng Quốc Tế & Đặc Tính Hóa Học
Độ hòa tan
Soluble
logP
-13.2
Dược Lực Học : Unfractionated heparin is a highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from 3000 to 30,000 daltons. Heparin is obtained from liver, lung, mast cells, and other cells of vertebrates. Heparin is a well-known and commonly used anticoagulant which has antithrombotic properties. Heparin inhibits reactions that lead to the clotting of blood and the formation of fibrin clots both in vitro and in vivo. Small amounts of heparin in combination with antithrombin III, a heparin cofactor,) can inhibit thrombosis by inactivating Factor Xa and thrombin. Once active thrombosis has developed, larger amounts of heparin can inhibit further coagulation by inactivating thrombin and preventing the conversion of fibrinogen to fibrin. Heparin also prevents the formation of a stable fibrin clot by inhibiting the activation of the fibrin stabilizing factor. Heparin prolongs several coagulation tests. Of all the coagulation tests, activated partial prothrombin time (aPTT) is the most clinically important value.
Cơ Chế Tác Dụng : Unfractionated heparin (UH) is a heterogenous preparation of anionic, sulfated glycosaminoglycan polymers with weights ranging from 3000 to 30,000 Da. It is a naturally occurring anticoagulant released from mast cells. It binds reversibly to antithrombin III (ATIII) and greatly accelerates the rate at which ATIII inactivates coagulation enzymes thrombin (factor IIa) and factor Xa. UH is different from low molecular weight heparin (LMWH) in the following ways: the average molecular weight of LMWH is about 4.5 kDa whereas it is 15 kDa for UH; UH requires continuous infusions; activated partial prothrombin time (aPTT) monitoring is required when using UH; and UH has a higher risk of bleeding and higher risk of osteoporosis in long term use. Unfractionated heparin is more specific than LMWH for thrombin. Furthermore, the effects of UH can typically be reversed by using protamine sulfate. Under normal circumstances, antithrombin III (ATIII) inactivates thrombin (factor IIa) and factor Xa. This process occurs at a slow rate. Administered heparin binds reversibly to ATIII and leads to almost instantaneous inactivation of factors IIa and Xa The heparin-ATIII complex can also inactivate factors IX, XI, XII and plasmin. The mechanism of action of heparin is ATIII-dependent. It acts mainly by accelerating the rate of the neutralization of certain activated coagulation factors by antithrombin, but other mechanisms may also be involved. The antithrombotic effect of heparin is well correlated to the inhibition of factor Xa. Heparin is not a thrombolytic or fibrinolytic. It prevents progression of existing clots by inhibiting further clotting. The lysis of existing clots relies on endogenous thrombolytics.
Dược Động Học :
▧ Absorption :
Heparin must be given parenterally as it is not absorbed through the gastrointestinal mucosa. It is usually given by iv infusion or deep sc injection. The onset of action is immediate after iv injection but can be delayed 20 to 60 minutes following sc injection. Plasma heparin concentrations may be increased and activated partial thromboplastin times (aPTTs) may be more prolonged in geriatric adults (older than 60 years of age) compared with younger adults.
▧ Volume of Distribution :
40-70 mL/min (approximately the same as blood volume) Although heparin does not distribute into adipose tissues, clinicians should use actual body weight in obese patients to account for extra vasculature.
▧ Protein binding :
Very high, mostly to low-density lipoproteins. It is also extensively bound by globulins and fibrinogens.
▧ Metabolism :
Liver and the reticulo-endothelial system are the sites of biotransformation. The metabolic fate of heparin is not well understood.
▧ Route of Elimination :
The drug appears to be removed mainly by the reticuloendothelial system. A small fraction of unchanged heparin also appears to be excreted in urine. Heparin cannot be eliminated by hemodialysis.
▧ Half Life :
1.5 hours. The plasma half-life of heparin increases from about 60 minutes with a 100 unit/kg dose to about 150 minutes with a 400 unit/kg dose.
▧ Clearance :
Adult Clearance = 0.43 ml/kg/min 25-28 weeks gestation = 1.49 ml/kg/min
Độc Tính : In mouse, the median lethal dose is greater than 5000 mg/kg. Another side effect is heparin-induced thrombocytopenia (HIT syndrome). Platelet counts usually do not fall until between days 5 and 12 of heparin therapy. HIT is caused by an immunological reaction that makes platelets form clots within the blood vessels, thereby using up coagulation factors. It can progress to thrombotic complications such as arterial thrombosis, gangrene, stroke, myocardial infarction and disseminated intravascular coagulation. Symptoms of overdose may show excessive prolongation of aPTT or by bleeding, which may be internal or external, major or minor. Therapeutic doses of heparin give for at least 4 months have been associated with osteoporosis and spontaneous vertebral fractures. Osteoporosis may be reversible once heparin is discontinued. Although a causal relationship has not been established, administration of injections preserved with benzyl alcohol has been associated with toxicity in neonates. Toxicity appears to have resulted from administration of large amounts (i.e., about 100–400 mg/kg daily) of benzyl alcohol in these neonates. Its use is principally associated with the use of bacteriostatic 0.9% sodium chloride intravascular flush or endotracheal tube lavage solutions.
Chỉ Định : Unfractionated heparin is indicated for prophylaxis and treatment of venous thrombosis and its extension, prevention of post-operative deep venous thrombosis and pulmonary embolism and prevention of clotting in arterial and cardiac surgery. In cardiology, it is used to prevent embolisms in patients with atrial fibrillation and as an adjunct antithrombin therapy in patients with unstable angina and/or non-Q wave myocardial infarctions (i.e. non-ST elevated acute coronary artery syndrome) who are on platelet glycoprotein (IIb/IIIa) receptor inhibitors. Additionally, it is used to prevent clotting during dialysis and surgical procedures, maintain the patency of intravenous injection devices and prevent in vitro coagulation of blood transfusions and in blood samples drawn for laboratory values.
Tương Tác Thuốc :
  • Acetylsalicylic acid Increased risk of bleeding.
  • Aliskiren Monitor therapy due to enhanced hyperkalemic effect of aliskiren.
  • Aprotinin Aprotinin, in the presence of heparin, has been found to prolong the activated clotting time (ACT) as measured by a celite surface activation method. The kaolin activated clotting time appears to be much less affected.
  • corticotropin-releasing factor Contraindication: Heparin may enhance the adverse/toxic effect of Corticorelin. Significant hypotension and bradycardia have been previously attributed to this combination. Corticorelin prescribing information describes a case in which a patient experienced a substantial fall in blood pressure and heart rate, resulting in asystole and requiring resuscitation.
  • Drospirenone Heparin can increase risk of hyperkalemia for patients on drospirenone
  • Drotrecogin alfa The potential benefits of drotrecogin alfa should be weighed against an increased risk of bleeding in patients receiving therapeutic doses of heparin. Monitor for bleeding during concomitant therapy, and immediately stop infusion of drotrecogin if clinically important bleeding occurs. In patients receiving prophylactic heparin doses, consider continuing this during drotrecogin.
  • Ginkgo biloba Additive anticoagulant/antiplatelet effects may increase bleed risk. Concomitant therapy should be avoided.
  • Ticlopidine Increased bleeding risk. Monitor aPTT.
  • Tobramycin Increased risk of nephrotoxicity
  • Treprostinil The prostacyclin analogue, Treprostinil, increases the risk of bleeding when combined with the anticoagulant, Heparin. Monitor for increased bleeding during concomitant thearpy.
Liều Lượng & Cách Dùng : Liquid - Intravenous
Liquid - Irrigation
Solution - Intraperitoneal
Solution - Intravenous
Solution - Subcutaneous
Dữ Kiện Thương Mại
Giá thị trường
Nhà Sản Xuất
  • Công ty :
    Sản phẩm biệt dược : Calcilean
  • Công ty :
    Sản phẩm biệt dược : Calciparine
  • Công ty :
    Sản phẩm biệt dược : Hepalean
  • Công ty :
    Sản phẩm biệt dược : Heparin LEO
  • Công ty :
    Sản phẩm biệt dược : Heparin Lock Flush
  • Công ty :
    Sản phẩm biệt dược : Liquaemin
  • Công ty :
    Sản phẩm biệt dược : Liquemin
  • Công ty :
    Sản phẩm biệt dược : Multiparin
  • Công ty :
    Sản phẩm biệt dược : Novoheparin
Đóng gói
Tài Liệu Tham Khảo Thêm
drugbank
http://www.drugbank.ca/drugs/DB01109
PubChem Substance
http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=46507594
KEGG Compound
http://www.genome.jp/dbget-bin/www_bget?cpd:C00374
ChemSpider
http://www.chemspider.com/Chemical-Structure.751.html
National Drug Code Directory
http://www.hipaaspace.com/Medical_Billing/Coding/National.Drug.Codes/PDF/0009-0268-01
PharmGKB
http://www.pharmgkb.org/drug/PA449855
Wikipedia
http://en.wikipedia.org/wiki/Heparin
RxList
http://www.rxlist.com/cgi/generic/heparin.htm
Drugs.com
http://www.drugs.com/heparin.html
... loading
... loading