Blood clots and embolisms are treated with blood thinners: medications that reduce clotting ability and help dissolve unwanted clots. Also known as anticoagulants, blood thinners are sometimes used as prophylactics, to help prevent clots from forming. People with heart arrhythmias, for instance, often take oral blood thinners on a daily basis to reduce the risk of strokes or other blood clotting complications. Heart arrhythmias increase the risk of clot formation in the heart because the arrhythmia can lead to abnormal blood flow in the chambers of the heart. This abnormal flow can lead to areas where the blood doesn’t move. When blood isn’t circulated it is more likely to coagulate.
Blood thinners inhibit coagulation, and hinder the body’s ability to stop bleeding. People taking warfarin, heparin, aspirin, or any other blood thinners, should inform their doctors and dentists before any surgical or dental work is performed.
Warfarin is one of the standard blood thinners, and one of the first choices used to treat blood clots. Warfarin is usually taken orally, so can be taken by the patient at home. This makes warfarin more convenient than the second most commonly used prescription blood thinner, heparin, which must be administered intravenously under medical supervision.
Warfarin may be prescribed to treat an isolated incident of blood clotting. Warfarin is also used for individuals who require regular, prophylactic anti-coagulant treatment.
Like all blood thinners, warfarin can cause easy bleeding or bruising. Warfarin can also cause birth defects and cannot be taken during pregnancy.
After warfarin, heparin is perhaps the second most common prescription blood thinner. As noted above, heparin must be injected, and its use must be carefully monitored. This requires increased medical care and monitoring, inconveniences that have limited heparin’s use as a blood thinner. Despite these drawbacks, heparin is still used to treat many clotting conditions because it works much faster than warfarin. Often, a patient with a clot will start out taking heparin for a few days and then transition to warfarin.
The latest formulation of heparin is easier to administer. Instead of intravenous injections, the new heparin, called low molecular weight heparin, can be injected subcutaneously. Low molecular weight heparin also does not require the same rigorous medical monitoring as older varieties of heparin. This allows the patient to self-administer low molecular weight heparin at home, increasing this blood thinner’s usefulness.
Heparin is safe to use while pregnant, unlike warfarin. Heparin and aspirin are being used to lower the chance of miscarriage and improve pregnancy outcomes in women with APS (antiphospholipid antibody syndrome). APS-related pregnancy failure rates remain high, however. Some pregnant women with APS appear to benefit from a combination of heparin, aspirin, and intravenous immunoglobulin.
Prophylactic aspirin use can help prevent deep vein thrombosis, thereby lowering the risk of circulation problems and embolism. An over-the-counter medication, aspirin’s active ingredient is acetylsalicylic acid.
Although aspirin is readily available, it should not be used as a blood thinner without the advice of a doctor. Aspirin can aggravate asthma, stomach ulcers, and kidney and liver disease. Aspirin is generally not recommended for pregnant women, but may be used under the supervision of a physician in special cases. If you take other medications, vitamins, or herbal supplements, aspirin may interact negatively with them.
GP IIb/IIIa Inhibitors and Clinical Trials
In addition to aspirin, heparin, and warfarin, new blood thinners may soon be available. Anticoagulant clinical trials testing a set of medications known as GP IIb/IIIa inhibitors are in progress. These new medications include tirofiban, eptifibatide, lambifiban, and abciximab. At present, these blood thinners can only be accessed through clinical trials.