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What is Deep Vein Thrombosis?

If you develop a blood clot in one of your deep veins, it’s called a deep vein thrombosis (DVT). The most common place for a DVT to develop is the leg – that is, in the larger vein that runs through the muscles of the calf and thigh – though other veins can sometimes also be affected, such as those in the arms or the stomach. But because the veins that are affected aren’t near the surface of the skin, you can’t see a DVT with the naked eye.

You may not have any symptoms, either. Those who do experience symptoms, however, may notice a swelling in the foot, ankle or leg (usually on one side), cramp-like pain in the affected leg (usually starting in the calf), pain in the foot and ankle, an area of skin that feels hot to the touch, or an area of skin that’s pale or red/blue in colour, often at the back of your leg below the knee.

If a DVT is left untreated it can cause a pulmonary embolism, which is where part of the blood clot breaks off and travels to your lungs, causing breathing difficulties and chest pain (around one in 10 people with an untreated DVT wil develop a pulmonary embolism (i) ). The most serious complication of DVT, a pulmonary embolism can – in the most severe cases – be fatal. Up to 40 percent of people who’ve been diagnosed with a DVT also develop post-thrombotic syndrome (ii), which can cause pain in your calf as well as swelling, a rash and sometimes ulcers on the calf too.

Are you at risk?

According to the NHS, each year one in every 1,000 people in the UK is affected by DVT (i). Your age can put you at risk, as DVT becomes more common as you get older (it becomes more common in people over the age of 40 (i) ). The following may also make you more susceptible:

  • Having previously had a DVT or pulmonary embolism.

  • Having a family history of DVT.

  • Having had surgery lasting more than an hour.

  • Having an illness or injury that affects your mobility.

  • Being pregnant.

  • Smoking.

  • Not drinking enough fluids (dehydration).

  • Taking the contraceptive pill or hormone replacement therapy (HRT)

  • Being obese or overweight (this increases pressure in the veins in your legs and pelvis).

  • Having severe heart disease or certain blood diseases.

  • Having varicose veins or an injury that has damaged your veins.

  • Having cancer, an inflammatory condition such as rheumatoid arthritis, an infectious disease such as hepatitis, or a condition that makes your blood abnormally ‘sticky’ or more likely to clot, such as Hughes syndrome or thrombophilia.

  • Having high cholesterol (some experts believe this may also be a risk factor for DVT) (iii) .

If any of these risk factors apply to you, it’s important to know the symptoms of DVT and pulmonary embolism. And if you notice any of these warning signs – whether or not you have a higher-than-normal risk – see your GP straight away or go to your local hospital’s A&E department.

How is DVT treated?

There are several tests that help diagnose a DVT, including a blood test (called the D-dimer test), an ultrasound scan and a venogram. The latter is an x-ray that looks at the pattern of a special dye injected into your foot that travels up the blood vessels of your leg.

If your results show that you have a DVT, the usual treatment is to take medicines called anticoagulants. Contrary to what most people think, anticoagulants – though often called blood-thinning medicines – don’t thin the blood as such. What they do, however, is to alter certain chemicals in the blood to stop a clot getting any bigger. They also help prevent part of a clot from breaking off and causing an embolism.

Most people who have a DVT have to take anticoagulants for at least three months, with a fast-acting injection given at the beginning of their treatment (this injection contains a medicine called heparin).

After the initial injection or injections, treatment often continues with warfarin tablets. However, anyone taking warfarin needs close monitoring, which means having frequent blood tests to determine whether or not you’re taking the right dose.

Warfarin alternatives

Doctors are also now prescribing newer anticoagulant medicines that remove the need for such strict monitoring and regular blood tests:

  • Rivaroxaban is recommended by the National Institute for Health and Care Excellence (NICE) as a possible treatment to help prevent DVT and also to treat DVT (iv). It works by preventing blood clots forming, and is usually prescribed for three months.

  • Apixaban, like Rivaroxaban, helps prevent the formation of blood clots. It is taken for at least three months.

  • Dabigatran works in a similar way to Apixaban, preventing blood clots from forming by interfering with a substance in your blood called thrombin.

  • Edoxaban also prevents your blood from clotting as quickly as usual, and works like Rivaroxaban by blocking a substance in your blood called factor Xa (or activated factor X). Like the previous three medications, it too is recommended by NICE (iv).

Surgical treatment is also available but isn’t routinely offered. For instance, an embolectomy can be performed to remove a blood clot from a vein or pulmonary artery. Another operation can be carried out to place a filter above the blocked leg vein to stop the clot from travelling up into the lungs. However it is only considered if someone is unable to take anticoagulant medication.

DVT prevention

If you have a DVT it can put your health at risk. So it’s a good idea to take certain steps to prevent one developing, especially if your chances of having one are higher than normal.

Quit smoking

Smoking increases the risk of blood clots because it can make it more likely that cells called platelets in the blood will stick together (when platelets clump together, the result is a clot). Giving up smoking, however, can improve your platelet function. If you need support with quitting, there are products that can help reduce your withdrawal symptoms, such as nicotine patches, lozenges and gum.

Eat healthily

Having a nutritious diet with at least five portions of fruit and vegetables each day and limited amounts of sugar and saturated fat is good for your overall health. A balanced diet will also provide a good amount of dietary fibre, including soluble fibre to help reduce your cholesterol levels.

Get active

Avoiding long periods of immobility can help prevent a DVT. If you have a sedentary job, try to get up and walk around for a few minutes every hour or so, and go for a brisk walk during lunchtime instead of sitting at your desk. Any type of physical activity where you get the circulation in the legs pumping is ideal. Aim for at least 150 minutes of moderate-intensity exercise each week (moderate intensity means you should feel warm and your heart should beat faster than normal).

Watch your weight

Aim to lose some of those excess pounds if you’re overweight and particularly if you’re obese (that is, if you have a body mass index of more than 30). The excess weight puts pressure on the veins in your legs and pelvis, which increases your DVT risk.

Stay hydrated

If you don’t drink the amount of fluid your body needs, you risk becoming dehydrated. This can increase your risk of developing a DVT because it makes your blood vessels narrow and your blood to become thicker. So try to drink at least six glasses of fluids every day – plain water is the healthiest choice because it contains no sugar or calories, but other drinks can count towards your daily fluid intake too (though try to avoid drinking too many caffeinated beverages, such as tea, coffee and some fizzy drinks, as they can make you produce urine more quickly than non-caffeinated drinks).

Meanwhile, if you’re going into hospital for an operation, your doctor will recommend measures to reduce your risk of developing a surgery-related DVT, including the following:

  • You should stop taking the contraceptive pill or HRT four weeks before your operation.

  • If your doctor thinks it’s necessary, you should also wear compression stockings during and after the operation to keep the circulation in your legs working normally.

  • Once your operation is over, you should start to move around as soon as possible.

  • Also after your operation, it’s important that you drink fluids to avoid becoming dehydrated.

When you leave hospital, you should continue to take regular gentle exercise (your healthcare team will give you details of how much exercise you should do as well as the safest type of exercise while you’re recuperating).

DVT: advice for travellers

Many people are aware that DVT is a risk for those travelling by plane. However, according to the Circulation Foundation, if you don’t have any of the risk factors for DVT, the risk of developing one – even on a long-haul flight – is very small (v).

Nevertheless it’s a good idea to take certain preventative measures, not just when you fly but also if you’re travelling by train, sea or by car (especially if your journey is going to last four hours or longer).

If you already have a high risk for DVT, seeing your doctor before you go away is essential, as there are drugs available that could help provide some protection. It’s also essential to invest in a pair of special support or compression socks – also known as flight socks – that you can wear when you’re travelling long distance that help to keep the blood in your legs pumping.

Whatever your level of risk, try to drink plenty of water during your journey and avoid having too much alcohol. Eat little and often when you’re travelling, and try to resist anything fatty or sugary. Try not to sit for hours with your legs bent – instead, stay active by taking short walks whenever you can (if you’re driving to your destination, plan plenty of rest stops where you can have a stroll to stretch your legs). And whenever possible, do some simple leg exercises regularly, such as flexing your ankles.

Eating certain foods that have an anticoagulant effect both before and during your journey may also be beneficial (however avoid eating anticoagulant foods if you’re taking blood-thinning medication). Try adding the following foods to your diet a couple of weeks before you fly:

Oily fish

One of the omega-3 essential fatty acids found in oily fish – namely eicosapentaenoic acid (EPA) – is thought to help prevent the platelets in blood from sticking together (vi). Plan some meals with salmon, mackerel, sardines, pilchards, herring, trout and fresh tuna in the run-up to your trip.


Substances called anthocyanidins found in dark red berries are also thought to have anti-clotting capabilities. So feast on blueberries, raspberries, blackberries and strawberries. Anthocyanidins are also found in red grapes.

Nuts and seeds

Vitamin E – found in nuts, seeds and whole grains – is also believed to be an effective anticoagulant (vii).


This spice may help keep your blood pumping, so it’s ideal to eat while you’re on the move. One way to get an instant chilli hit is to add some pepper sauce to your meal.


Natural remedies to prevent DVT

In addition to the lifestyle measures you can put in place to reduce your risk of developing a DVT – including eating healthily, taking sufficient exercise and reducing your weight (if necessary) – there are a few natural remedies that may help too. These include the following:

Butcher’s broom

Commonly found in woods and bushes, the root of this shrub-like evergreen plant is often used to treat varicose veins thanks to chemicals it contains that are believed to constrict blood vessels. Butcher’s broom is also used in Germany to treat chronic venus insufficiency, a condition where your leg veins aren’t able to pump blood back to your heart. Many natural health practitioners also recommend butcher’s broom for DVT prevention as it’s thought to have strong anti-inflammatory properties and may also boost blood circulation.

Horse chestnut

Like butcher’s broom, horse chestnut is often used as a treatment for venous insufficiency. It may also help with inflammation and increase blood circulation. There is some evidence that horse chestnut extract may help to contract veins and arteries, providing a similar effect to that of using compression socks (viii).

High-strength anthocyanidins

These antioxidant compounds (including their derivatives anthocyanins) are found in dark-skinned fruits such as blueberries, cranberries, raspberries, blackberries and red grapes, as well as vegetables such as red cabbage, red onions and aubergines.

Available in supplement form, anthocyanidins are thought to help prevent clotting and strengthen the walls of veins and capillaries as well as strengthen and repair collagen. And by reducing fluid leaking into tissues surrounding blood vessels, they may help to reduce and/or prevent swelling. Some natural health practitioners recommend anthocyanidins to reduce the risk of DVT following surgery.

For more articles on a range of other common health conditions, simply visit our health library.



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  3. , , et al. . Hypercholesterolemia as a risk factor for deep-vein thrombosis. Thromb Res. 1;88(1):67-73. Available online:

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  6. , Acute Supplementation With Eicosapentaenoic Acid Reduces Platelet Microparticle Activity in Healthy Subjects. J Nutr Biochem.23(9):1128-33. Available online:

  7. , , , , et al. Horse chestnut extract contracts bovine vessels and affects human platelet aggregation through 5-HT(2A) receptors: an in vitro study. Phytother Res. Sep;24(9):1297-301. doi: 10.1002/ptr.3103. Available online:


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Disclaimer: The information presented by Nature's Best is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications.

Our Author - Christine Morgan


Christine Morgan has been a freelance health and wellbeing journalist for almost 20 years, having written for numerous publications including the Daily Mirror, S Magazine, Top Sante, Healthy, Woman & Home, Zest, Allergy, Healthy Times and Pregnancy & Birth; she has also edited several titles such as Women’ Health, Shine’s Real Health & Beauty and All About Health.

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