Blood clots occur when groups of blood cells bunch up and stick together. Clots can be caused by injury or disease. Depending on where they form, blood clots can cause tissue damage resulting in serious injury or even death. Dissolving clots is the best way to prevent or minimize damage, and it can be very effective, if done in time. This process is called thrombolysis, and is accomplished by the use of medications that work to digest clots, causing them to dissolve.
There are three main types of thrombolytic agents, the medicines that work to dissolve blood clots. These agents are effective because they cause an increase in the amount of plasmin in the blood. Plasmin is a naturally occurring agent that dissolves clots. It is created from plasminogen by various enzymes in the body in response to the presence of blood clots or other factors.
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The first of these three agents is streptokinase, a medication created from streptococci bacteria. Streptokinase works well to dissolve blood clots and is the least expensive of the thrombolytic agents. The problem with this drug is that it has been known to cause negative reactions in some patients, particularly unfavorable immune system responses, so it cannot be used in all situations.
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Urokinase is another agent used to dissolve blood clots. It exists naturally in the human system, so there are no problems with immune system rejection, making it safer to use. The down side is that it is difficult to purify urokinase, making the agent a costly choice. When this medicine is used to dissolve blood clots, it is normally combined with other drugs because of it high cost.
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The third agent is tissue plasminogen activator (tPA), a medication discovered around 1980 and originally derived from human uterine tissue. tPA has been used successfully to dissolve clots, providing useful therapy for deep vein thrombosis (DVT), heart attack, pulmonary embolism and stroke. The biggest drawback of this medicine is its high cost. Researchers have had some success in cloning hamster genes to create large quantities of tPA, which should help to bring the cost down significantly over time.
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Anticoagulant drugs help to dissolve blood clots by preventing them from getting bigger and allowing the body’s natural defenses to actually shrink the clot. Coumadin, aspirin and heparin are all used to prevent clots from getting bigger. A study by the University of Colorado Health Sciences Center also concluded that aerobic exercise increases the amount of tPA in the blood, helping to dissolve blood clots. Whichever method is used, blood clots are serious and should be treated as quickly as possible to minimize the potential risks.