What Is "Economy Class Syndrome"? A Traveler's Guide
"Economy class syndrome," sometimes called traveler's thrombosis, is an informal name for a blood clot that develops during or after long-distance travel. The term dates to the 1990s, when the pattern was noticed among air travelers in cramped seating.
It isn't a formal diagnosis. The underlying condition is deep vein thrombosis (DVT), a clot that forms in a deep vein, usually in the leg. The CDC explains that part of a clot can break off and travel to the lungs, causing a blockage called a pulmonary embolism, and that while these clots are rare, they're serious.
Why it happens
The CDC explains that sitting for a long time without getting up and walking around can cause blood to pool in the leg veins, which can lead to clots.
Although it's most associated with flying, the CDC notes that travel by car, bus, or train carries the same consideration, because the common factor is sitting still for hours rather than anything specific to aircraft.
What to watch for
Symptoms can appear during a trip or in the days and weeks afterward. The CDC advises travelers to know the signs of blood clots so they can recognize them. Possible signs in the leg include swelling, pain or tenderness, skin that feels warm, and skin that looks red or discolored. Signs that a clot may have traveled to the lungs include difficulty breathing, chest pain that worsens with a deep breath, a rapid heartbeat, and coughing up blood.
If you notice these symptoms, seek medical attention promptly. Don't wait to see whether they pass.
Who's at higher risk
The CDC notes that your level of risk depends on how long you travel and whether you have other risk factors. Factors that can raise risk include a previous blood clot, a family history of clots, recent surgery or injury, limited mobility, pregnancy and the period after birth, estrogen-containing birth control or hormone therapy, obesity, older age, and certain chronic conditions including cancer.
If several of these apply to you, that's a conversation worth having with your doctor before a long trip, not something to manage on your own.
How to lower your risk on a long trip
The CDC suggests several practical steps:
- Get up and move. Walk the aisle when it's safe, and build stretch breaks into a long drive.
- Exercise in your seat. Simple ankle and calf movements keep the muscles working while you're seated.
- Know the symptoms so you can act quickly if something feels wrong.
- Talk to your doctor before departure about compression stockings or medication if you have additional risk factors. The CDC specifically notes that taking aspirin to prevent travel-related clots is not recommended.
On compression specifically, a Cochrane review of flights lasting four hours or more found that wearing compression stockings helped reduce symptomless DVT by increasing blood flow velocity in the calf veins. Worth noting for balance: Scottish guidance (SIGN) doesn't routinely recommend compression stockings for long-haul travel, so medical bodies differ on this. Your doctor is the right person to weigh it for your situation.
Comfort on a long travel day
Separately from any medical question, long travel days are hard on your legs. Loose clothing, comfortable shoes, drinking water, and getting up when you can all make the trip more pleasant.
Many travelers also wear compression socks on flights simply because their legs feel better at the end of the journey. Our Knee-High Compression Socks come in 15-20 mmHg with a soft, breathable knit that's easy to wear from the airport to the hotel. ✈️🧦
If you have any of the risk factors above, ask your doctor what's right for you before relying on compression on a long trip.
Sources
CDC — Understanding Your Risk for Blood Clots with Travel
CDC — Blood Clots During Travel
NIHR Evidence — Long-haul flyers could reduce risk of leg blood clots with compression stockings
NHS — Varicose Veins