Blood drugs Flashcards
What is thrombosis?
The formation of an unwanted clot within a blood vessel.
List some thrombotic disorders.
- Acute myocardial infarction
- Deep vein thrombosis
- Pulmonary embolism
- Acute ischemic stroke
What types of drugs are used to treat thrombotic disorders?
- Anticoagulants
- Fibrinolytics
What is hemophilia?
A bleeding disorder treated with transfusion of Factor VIII prepared by recombinant DNA techniques.
How is vitamin K deficiency treated?
With dietary supplements of vitamin K.
What is iron-deficiency anemia?
Anemia caused by nutritional deficiencies that can be treated with dietary or pharmaceutical supplementation.
What distinguishes a thrombus from an embolus?
A thrombus adheres to a vessel wall, while an embolus is a clot that floats in the blood.
What is the primary risk associated with thrombi and emboli?
They may occlude blood vessels and deprive tissues of oxygen and nutrients.
What typically triggers arterial thrombosis?
Surface lesions on endothelial cells caused by atherosclerosis.
What is characteristic of arterial thrombosis?
It usually consists of a platelet-rich clot.
What typically triggers venous thrombosis?
Blood stasis or inappropriate activation of the coagulation cascade.
What is characteristic of venous thrombosis?
It typically involves a clot that is rich in fibrin, with fewer platelets.
What initiates hemostasis after vascular injury?
A complex series of interactions between platelets, endothelial cells, and the coagulation cascade.
What is vasospasm?
The initial response of a damaged blood vessel to prevent further blood loss.
Name a platelet inhibitor.
- Abciximab (REOPRO)
- Aspirin (various)
- Cilostazol (PLETAL)
- Clopidogrel (PLAVIX)
- Dipyridamole (PERSANTINE)
- Eptifibatide (INTEGRILIN)
- Prasugrel (EFFIENT)
- Ticlopidine (TICLID)
- Tirofiban (AGGRASTAT)
Name an anticoagulant.
- Argatroban (ARGATROBAN)
- Dabigatran (PRADAXA)
- Dalteparin (FRAGMIN)
- Enoxaparin (LOVENOX)
- Fondaparinux (ARIXTRA)
- Heparin (HEP-LOCK, HEPFLUSH-10)
- Lepirudin (REFLUDAN)
- Tinzaparin (INNOHEP)
- Warfarin (COUMADIN, JANTOVEN)
What are thrombolytic agents?
- Alteplase (tPA) (ACTIVASE)
- Reteplase (RETAVASE)
- Streptokinase (STREPTASE)
- Urokinase (KINLYTIC)
What is aminocaproic acid used for?
It is used in the treatment of bleeding.
What is the role of vitamin K in treating bleeding disorders?
It is used as a dietary supplement for vitamin K deficiency.
How is anemia treated?
- Cyanocobalamin (B12)
- Erythropoietin
- Folic acid
- Iron
What medication is used to treat sickle cell anemia?
- Hydroxyurea (DROXIA, HYDREA)
- Pentoxifylline (TRENTAL)
What are resting platelets?
Resting platelets are platelets that circulate freely in the absence of injury, monitoring the integrity of the endothelium.
What do healthy, intact endothelial cells release?
Healthy, intact endothelial cells release prostacyclin into plasma.
How does prostacyclin affect platelets?
Prostacyclin binds to platelet membrane receptors, causing the synthesis of cAMP, which stabilizes inactive GP IIb/IIIa receptors and inhibits the release of granules containing platelet aggregation agents.
What is the role of cAMP in resting platelets?
Elevated levels of intracellular cAMP are associated with a decrease in intracellular calcium, preventing platelet activation.
What happens when endothelial cells are damaged?
Damaged endothelial cells synthesize less prostacyclin, leading to lower levels of intracellular cAMP and increased platelet aggregation.
What are some chemical mediators synthesized by endothelial cells?
Prostacyclin and nitric oxide are synthesized by intact endothelial cells and act as inhibitors of platelet aggregation.
What is the effect of the drug dipyridamole?
Dipyridamole inhibits the enzyme phosphodiesterase, which inactivates cAMP, thereby prolonging its active life.
What triggers platelet activation?
Platelet activation can be triggered by thrombin, thromboxanes, and collagen.
What do activated platelets release?
Activated platelets release chemical mediators such as thromboxane A2, ADP, and serotonin.
What is the role of activated platelets in hemostasis?
Activated platelets cover and adhere to exposed endothelial surfaces, contributing to the formation of a hemostatic plug.
What are thromboxanes?
Thromboxanes are signaling molecules involved in platelet activation and aggregation.
What happens in an intact, normal vessel regarding thrombin and thromboxane levels?
Circulating levels of thrombin and thromboxane are low, and the intact endothelium covers the collagen in the subendothelial layers.
What is the result of unoccupied platelet receptors in a normal vessel?
Platelet activation and aggregation are not initiated.
What triggers platelet activation when the endothelium is injured?
Platelets adhere to and cover the exposed collagen of the subendothelium.