Antiplatelet drugs Heparin

Heparin and antiplatelet drugs are therefore used in various forms of angina to help prevent infarction. When administered with the traditional anti-anginal medications, these anticoagulants can help decrease morbidity and mortality in people with ischemic heart disease. For more details on the effects of anticoagulant medications, please refer to Chapter 25. 

E3 monoclonal antibody to GPIIb/llla (abciximab) is very useful as an antiplatelet drug in high-risk ACSs and PCI, It can be used in conjunction with reduced levels of heparin and with aspirin (Table I), Patients may uncommonly experience sudden severe thrombocytopenia within the early hours of treatment as a side effect. 

MI usually develops after rupture or erosion of an atherosclerotic plaque within a coronary blood vessel. At this site, the clotting cascade is activated and the resultant thrombus occludes the lumen. In all patients under suspicion of MI, immediate therapy has to be initiated by the emergency physician. To relieve the patient from severe pain and anxiety, morphine and a benzodiazepine need to be given. Antiplatelet drugs and heparin are necessary for preventing further formation of thrombi. Nitroglycerin can be used to reduce cardiac load. When blood pressure and heart rate have stabilized, a p-blocker can be administered to lower cardiac 02 consumption and the risk of arrhythmias. Infusion of lidocaine is required to counter the threat of arrhythmias. The chance of survival of the MI patient depends on the interval between the onset of infarction and the start of therapy. 

CcHnbination modalities for die mangmiait of arterial and venous thrombosis are currently being explored. While these modalities provide an increase in the efficacy, safety considerations are of cmcial importance. Aspirin is commonly used with various anticoagulants. Many other antiplatelet drugs, such as ticlopidine, are also being combined with heparin, himdin, GP Ilb/IIIa inhibitors and aspirin itself... 

Peripheral arterial occlusion. Heparin may prevent extension of a thrombus and hasten its recanalisation it is commonly used in the acute phase following thrombosis or embolism. There is no case for treating ischaemic peripheral vascular disease with an oral anticoagulant (for prevention, see Antiplatelet drugs). 

Drotrecogin alfa should be used with care in patients receiving heparin, thrombolytic drugs, oral anticoagulants, glycoprotein Ilb-IIIa inhibitors, and aspirin or other antiplatelet drugs (6). 

Susceptibility factors previous heparin therapy, co-administration of antiplatelet drugs or oral anticoagulants... 

In two of the five spontaneous bleeding episodes described in Heading 4, medications that can affect platelet function or prothrombin time (PT) (i.e., aspirin and warfarin) were involved. Because GB is known to be an inhibitor of PAF (41), in theory GB could interact with antiplatelet drugs (e.g., aspirin, nonsteroidal anti-inflammatory drugs, clopidogrel, ticlopidine, dipyridamole) or anticoagulants (e.g., warfarin, heparin). EGb 761 was shown to potentiate the antiplatelet effect of ticlopidine in rats (42). However, in two studies in humans, the coadministration of GB with warfarin had no effect on either international normalized ratio or warfarin metabolism (43,44). 

It is unclear to what extent the antiplatelet effect of heparin contributes to the hemorrhagic complications of treatment with the drug. Heparin clears lipemic plasma in vivo by causing the... 

Antiplatelet drugs increase the risk of bleeding, and the risk is likely to be inereased further in patients who are anticoagulated with heparin or LMWHs. 

Therefore some antiplatelet drugs can have beneficial additive effects with other antiplatelet drugs that act via different mechanisms. Furthermore, other drugs such as dextrans, heparin, some prostaglandins and sulfinpyrazone also have some antiplatelet activity. 

The manufacturer of abciximab recommends caution when it is used with other drugs that affect haemostasis, such as heparin, warfarin, thrombolytics and antiplatelet drugs other than aspirin, such as dipyridamole and ticlopidine4 ... 

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