Patient information from BMJ

DVT and long-distance travel

Last published:Jul 06, 2020

If you have deep vein thrombosis (DVT), it means a blood clot has formed in one of your deep veins, most likely in your leg. Parts of the clot can break off and travel to your lungs, which can be dangerous.

DVT is more likely if you can't or don't move about for long periods. This may be why people have a greater chance of DVT if they go on a long journey, such as a long flight. 

If you've had DVT before, or if you are more likely than most people, you should talk with your doctor about ways to prevent it before you go on a long trip. Things that may increase your chance of DVT include:

• being older

• being very overweight (obese)

• having had a recent surgery or injury

• having a blood clotting disorder

• being pregnant

• taking hormone therapy, and

• having cancer.

You may need to take medications to reduce your chance of blood clots. Or you may need to wear special elastic stockings called compression stockings.

These stockings help to keep the blood flowing smoothly through the veins in your legs, so it’s less likely that a clot will form. Your pharmacist can measure you to ensure you buy the right size of stockings. 

Whether or not you are at high risk, you can do exercises and other things while you travel that may help prevent DVT. 

Here are some of the things experts recommend when travelling.

• Don't take sleeping pills. These pills can make you fall deeply asleep so that you don’t move your legs at all.

• Don't drink alcohol, but do drink extra water and other fluids.

• Try to exercise your legs while seated. Bend and straighten your legs, feet, and toes while sitting down, every half hour. Make a circle pattern with each foot in turn.

• Press the balls of your feet down hard against the floor or a footrest to increase the blood flow in your legs.

• Avoid sitting still for long periods. If possible, take short walks around the cabin of your aeroplane or train compartment every 30 to 60 minutes. If you are in a car or bus, take a short walk whenever you stop for a break. If you are driving, make sure you schedule regular breaks. 

Even if you are not at high risk, you may want to think about wearing compression stockings. But the stockings are not suitable for everyone, so ask your doctor about them first. 

You should get medical help quickly if you get symptoms of DVT. The main symptoms are swelling or pain in the calf or thigh of one leg, or both swelling and pain. If a clot has travelled to your lungs, you may get chest pain or shortness of breath. 

If you get DVT because of sitting still on a long-distance journey, you may not notice any pain or swelling right after the trip. It can take hours or even days or weeks for you to get any symptoms.