Deep Vein Thrombosis
- These clots form in veins deep inside the leg. The veins involved cannot be seen.
- These most commonly form in the leg veins but can occur in other parts of the body such as the arms or intestines.
Your doctor may suspect that you have a deep vein thrombosis if you have some of the following symptoms.
- Pain - this can be anywhere in the leg but is commonly felt in the calf.
- Swelling - often most obvious around the ankle, but can involve the whole leg.
- Redness - a slight dusky discolouration of the leg is common.
- Warmth - the leg feels warm to touch.
These are the most common symptoms of a deep vein thrombosis but they are not all present in all cases.
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Treatment
Deep vein thrombosis and pulmonary embolus are treated with drugs called anticoagulants. These drugs do not dissolve the clot but work by slowing the normal clotting mechanism. This allows your body to naturally break down the blood clot. Two anticoagulants are commonly used: heparin and warfarin. Most patients receive both of these drugs to treat a blood clot, but some patients may remain on heparin alone.
Usual treatment
This usually consists of a short course of heparin followed by several months of warfarin treatment.
- Low molecular weight heparin given as an injection under the skin for 5 to 7 days.
- Treatment is given once or twice a day
- Warfarin tablets for 3 to 6 months.
- Tablets taken once a day in the evening
- Regular blood tests required to check warfarin dose.
Heparin
Heparin is the first drug that you will receive. It is given as an injection under the skin (subcutaneous). This type of heparin is often referred to as "low molecular weight heparin". Heparin gets into the blood stream very quickly and starts to work within a few hours of your first injection. The dose is calculated from your weight. You will have an injection once or twice a day for at least 5 days.
Sometimes a different form of heparin is given via a drip.
Warfarin
Warfarin is taken as a tablet given once a day. It is recommended that it is taken in the evening. You will need to be on warfarin for several months to treat a deep vein thrombosis or pulmonary embolus. Warfarin is normally started very soon after heparin, but it takes 5 to 7 days to have its full effect as an anticoagulant. The amount of warfarin needed to treat a blood clot varies between people. To check the warfarin level, a blood test called the INR is done regularly. This test will show how much warfarin you need to take. Once the level is stable the INR test will be done less often.
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