Prevent DVT (deep vein thrombosis) when you travel

Travel-related DVT is rare in healthy people. But if you're travelling long distance, there are several ways you can reduce your risk.

DVT (deep vein thrombosis) is when a blood clot forms in a deep vein, usually in the leg, and blocks blood flow. It can happen after sitting still during long journeys by bus, train, or air.

Read more about the symptoms and treatment of DVT.

General advice to reduce your risk of travel-related DVT

If you're travelling for 3 hours of more by plane, train or car, take these steps during the journey to reduce your risk of DVT:

• wear loose, comfortable clothes
• do calf exercises at least every half hour – raise your heels, keeping your toes on the floor, then bring them down 10 times. Then raise and lower your toes 10 times
• walk around whenever you can
• drink plenty of water
• do not drink alcohol or take sleeping pills

Who's at extra risk of travel-related DVT?

Some health conditions and other things may increase your risk of DVT on long journeys. You're at higher than average risk of DVT if you:

• have a history of DVT or pulmonary embolism
• have cancer
• have had a stroke
• have heart disease
• have an inherited tendency to get blood clots
• have had recent surgery – especially in the tummy, pelvic region or legs
• are very overweight
• are pregnant or you've had a baby in the previous 6 weeks
• take oestrogen-containing medicines such as HRT (hormone replacement therapy) or the combined contraceptive pill

If you think you're at extra risk of DVT, see your GP before you travel. You might have to take extra precautions such as wearing flight socks or compression stockings during the journey.

Flight socks and compression stockings

Wearing compression stockings or flight socks during journeys of 3 hours or more can help prevent DVT if you're at an increased risk.

The stockings or socks are usually knee length; compression stockings can also be thigh high.

They work by putting gentle pressure on your leg and ankle to help blood flow.

Compression stockings and flight socks come in different sizes with different levels of compression. Class 1 stockings have the lowest compression (with a pressure of 14-17 mmHg at the ankle) and are generally sufficient to prevent DVT.

It's important that compression stockings are worn correctly. Ill-fitting stockings could further increase the risk of DVT.

You can buy compression stockings and flight socks from pharmacies, airports and many high-street shops and pharmacies. They can also be prescribed by a GP. 

Get advice on size and proper fitting from a pharmacist or another health professional.

Travelling while recovering from a previous DVT

If you had DVT recently, you're probably taking medicine, such as apixaban or warfarin, to prevent new blood clots.

If that's the case, your medicine will protect you from getting another DVT while you're taking it. So, your risk of getting a DVT from travelling is low and there should be no reason why you cannot travel, including long haul. Speak to your doctor if you have any concerns before you travel.

If you had a DVT within the last 2 weeks, get the all-clear from your doctor before travelling.

Read a traveller's experience of getting DVT from flying.

Page last reviewed: Thu Apr 2019 Next review due: Mon Apr 2022