Anticoagulation UK

Deep Vein Thrombosis (DVT)

Deep Vein Thrombosis (DVT) is when a blood clot develops inside a vein.

If a piece of the clot breaks off and travels to the lungs this is called a pulmonary embolism (PE).

The collective name for both DVT and PE is Venous thromboembolism (VTE).

There are many things that can cause a DVT, the main risk factors are:


*It should also be noted that some people will have a DVT for no apparent reason.

In the UK one in twenty people will have a blood clot during their lifetime

Symptoms of a Deep Vein Thrombosis and Pulmonary Embolism

Deep Vein Thrombosis (DVT)

In some cases, there may be no symptoms of DVT. If symptoms do occur they can include:

  • pain, swelling and tenderness in one of your legs (usually your calf) but DVT can also occur in the thigh and the arms.
  • a heavy ache in the affected area 
  • warm skin in the area of the clot 
  • red skin, particularly at the back of your leg below the knee 

DVT usually (although not always) affects one leg. The pain may be worse when you bend your foot upward towards your knee.

Pulmonary embolism (PE)

If the DVT is not treated approximately one in 10 people with a DVT will develop a pulmonary embolism. A PE is a very serious condition which needs urgent medical attention. Untreated a PE can cause death.

  • breathlessness – which may come on gradually or suddenly 
  • chest pain – which may become worse when you breathe in 
  • sudden collapse 
  • sweating
  • light headedness – feeling faint

How can you help to prevent a DVT in your daily life?

There are some risk factors that you can’t do anything about such as age and family history. But you can help to reduce your risk by doing the following:

  • Eating a healthy and varied diet that includes plenty of fruit, vegetables, beans, pulses and fish
  • Drinking plenty of water so you do not become dehydrated
  • Keep moving, take regular walks. If you sit at a desk for work get up and move around for a few minutes every two hours
  • If you smoke STOP

How can you Help avoid a travel related DVT ?

The following suggestions apply for any long journey, such as coach, train car or plane, and also when sitting for any lengthy period:

  • Keep your legs and feet active - every half hour, bend and straighten them to keep the blood circulating
  • Press down on the balls of your feet, then raise the heels to help increase the blood flow in your legs
  • Don't cross your legs
  • Exercise your chest and upper body frequently
  • Do deep breathing exercises to help improve circulation
  • Walk up and down the aisles frequently
  • If you are on a long flight which has refuelling stops, take the opportunity to leave the plane and walk about
  • Drink plenty of water - preferably a glass every hour
  • Avoid alcohol - or, if you must, take only small amounts
  • Alcohol will cause dehydration and sleepiness
  • Avoid sleeping pills - they will cause you to be immobile for long periods
  • Try not to sleep for too long in a cramped position - move about as much as possible and stretch out
  • Make sure you have had plenty of rest before you make a lengthy journey so that you are not too tired

Read more information in our 'Guide to Deep Vein Thrombosis (DVT)', which can be downloaded below.


PLEASE NOTE: The information in this leaflet is for guidance only. If you require advice in relation to a specific health condition, treatment or drug therapy relating to the conditions referred to in this leaflet then please speak to your doctor, nurse or pharmacist.

DVT Guide