Economy class syndrome (DVT)

Many doctors agree that taking a long haul flight in cramped conditions can sometimes lead to blood clots, or deep vein thrombosis (DVT) - often called 'economy-class syndrome'.

DVT blood clots develop in the legs and can break away and lodge in the lungs, causing a pulmonary embolism that blocks the blood flow. One study showed that one in ten passengers developed a blood clot following a long haul flight, another put the number 1% (equivalent to 4 people on every jumbo jet).

However, other than for high risk groups, the risk of a fatal clot is small and there are some things you can do to reduce the risk of DVT.

Before the flight

1. Some people are more at risk than others, including those with high blood pressure, a heart condition, cancer (or had treatment for cancer in the past), a hip or knee replacement in the last 3 months, those that have suffered a stroke, previous DVT or have a known clotting tendency. Seek medical advice before you fly.
2. If you are 6ft or over, try to book seats with more leg room. On some airlines the cost extra (anywhere between £5 and over £25) but are worth the investment.

In the air

1. Make yourself comfortable in your seat
2. Exercise is important during flights, whatever class you are travelling in. Take a walk in the aisles at least every hour to keep the blood circulating.
3. Stretch your legs regularly when you're sitting down. Rotate your ankles and wriggle your toes.
4. Drink plenty of water and cut down on alcohol, coffee and salty snacks such as peanuts and crisps as they dehydrate you.
5. avoid taking sleeping pills, which also cause immobility.
6. Consider wearing flight socks (special support stockings) to help your circulation during flights.
7. Take advantage of refueling stopovers where it may be possible to get off the plane and walk about
   drink plenty of water
8. Some doctors suggest taking a low-dose aspirin as it thins the blood, reducing the risk of DVT. However, recent studies suggest that asprin may not help but heparin (a blood thining agent) can be prescribed by a GP.

   After the trip

For the vast majority of air passengers there will be no problem. If, however, you do develop swollen painful legs especially where one is more affected than the other, or breathing difficulties (shortness of breath or chest pain) see a local doctor urgently or go to the nearest Accident and Emergency Department.

Who are the high risk groups?

Anyone who has has recent surgery, a stroke, a family history of blood clots, is taking HRT or is on the pill.