First described by Maurice Raynaud in 1862, Raynaud's is thought to affect as many as 10 million people in the UK. It causes severe pain in the extremities when exposed to temperature change.

What causes it?

Raynaud's is described as either primary, the most common form with no apparent cause, or secondary, when it's associated with an underlying disease, such as scleroderma, rheumatoid arthritis, Sjorgren's syndrome or systemic lupus erythematosus.

Who's affected?

Raynaud's affects nine times as many women as it does men. It can be hereditary - when this is the case, it tends to be a milder form.

It's quite common in teenagers, although many are only affected for a few years before it disappears when they're in their early 20s.

What are the symptoms?

Stress or a change in temperature interrupts the blood supply to the extremities triggering the symptoms. These usually affect the fingers and toes, but the ears and nose can be involved too.

The skin turns white, then blue (for some people) before going bright red. This final stage is accompanied by severe pain and occasionally numbness or tingling.

People with Raynaud's may have to avoid everyday activities for fear that exposure to temperature change will trigger symptoms. Going out in cold weather is an obvious example. But just getting something from the fridge or holding a cold drink may be all it takes to trigger an attack.

What's the treatment?

People who experience mild attacks usually only need to ensure they avoid temperature changes and wear warm clothing to protect them from the cold. Many people find having portable heating devices, such as warmers for gloves, socks or pockets, invaluable.

Regular exercise is a good way of stimulating the circulation. Eating regularly throughout the day, in particular hot meals and drinks, helps. Not smoking is essential.

There are many simple and imaginative ways people with Raynaud's can make life easier for themselves. Wearing oven gloves when using the fridge or freezer, for example, or putting a foil-wrapped baked potato in each coat pocket when going out.

In more severe cases, when attacks are frequent, prolonged and prevent people getting on with life, a variety of medicines can be used to help improve circulation. Some people also benefit from taking evening primrose oil, ginger, garlic, and vitamins C and E.