DVT on long-haul flights and who actually needs compression socks

Trek Guide About 1 in 6,000 travellers get a clot after a flight over four hours; most already had a risk factor. Walk the aisle. Stockings are for higher-risk… By Anjali Shrestha · Sep 27, 2026 Read the full story

For a healthy traveller, the risk of a blood clot on a long-haul flight is small: about 1 in 6,000 for a journey of more than four hours, according to the World Health Organization. The risk is real but concentrated. The US Centers for Disease Control and… Travel Himalaya Nepal · News Read the full story

How big the risk actually is

The chance of a clot after one long flight is low, and most of it sits with people who were already at risk. The WHO's WRIGHT research project found that the risk of venous thromboembolism — a deep vein thrombosis (DVT) in the leg, or a pulmonary embolism… Travel Himalaya Nepal · News Read the full story

Who is actually at risk

Most travel-related clots happen to people with at least one existing risk factor; the CDC puts the share at 75—99%. One study it cites found that 20% had five or more. The CDC and the NHS list broadly the same factors: a previous clot, or a family history of… Travel Himalaya Nepal · News Read the full story

What works on the plane

Walking the aisle, calf exercises and an aisle seat are the measures every agency recommends; stockings and medicine are for people at increased risk only. The evidence is thinner than the confident advice suggests, and the CDC Yellow Book says so plainly… Travel Himalaya Nepal · News Read the full story

Warning signs after you land

A clot can appear days or weeks after the flight, so a painful swollen leg or sudden breathlessness in the following month needs urgent attention. The CDC says most appear within one to two weeks, and that about half of people with a DVT have no symptoms at… Travel Himalaya Nepal · News Read the full story

Why this matters on a Nepal trek

The weeks after a long flight overlap with a trek, so breathlessness or a swollen calf on the trail should never be written off as altitude or a hard day. Most Annapurna and Everest itineraries start within days of landing in Kathmandu, inside the window when… Travel Himalaya Nepal · News Read the full story

The verdict

If you are healthy and have no risk factors, you need no stockings and no medicine — just move, choose the aisle and know the warning signs. If you have had a clot, recent surgery, a pregnancy, cancer treatment or take oestrogen, talk to your doctor before… Travel Himalaya Nepal · News Read the full story

Keep reading

Seat, kit and timing for the long way to Kathmandu. The symptoms that mean stop climbing, and when to descend. What to carry, and what the lodges will not have. The evidence behind patches, tablets, ginger and wristbands. Sources: World Health Organization… Travel Himalaya Nepal · News Read the full story

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