Varicose veins are common – although more so in women than in men. They are swollen veins that bulge under the skin, looking dark blue like large grapes and rather unappealing. NHS budgets mean that you can only get treatment if they really hurt or develop complications and not because you don't like the look of them. So is there anything you can do to prevent them or to stop them getting worse?

What are they?

You can get varicose veins in any vein theoretically but they usually occur in your leg veins because they take the most pressure. They are collections of venous blood. Blood gets carried back to the heart in the veins, which have valves to prevent backflow as the blood is moving upwards, against gravity. If the valves don't work the blood starts pooling. Your legs have deep veins within the muscles and more superficial veins beneath the skin. The leg muscles, by moving, help to push the blood through the veins towards the heart. But if the valves are damaged in the superficial veins then blood collects in them.

What causes them?

No one knows exactly why valves get damaged. They may get weaker with age. If you stand for a long time your blood may pool in your leg veins. Pregnancy increases the blood volume, and therefore the likelihood of varicose veins, but genetics is thought to play a large role. About half of people with varicose veins have family members with them. Overweight people have an increased risk because the veins are under more pressure.

What complications do they cause?

Varicose veins usually upset people because they look unsightly but they can also cause pain and aching. The skin over varicose veins gets dry and can develop eczema. It can also break down to form ulcers. Sometimes they can bleed if you bump your leg.

How do I treat them?

Don't make them worse by standing for long period, or crossing your legs, which impedes blood flow in the veins. If you have dry skin over your varicose veins make sure you use lots of moisturiser to avoid your skin breaking down. You should see your GP first to make sure your circulation is OK before trying any treatments – he or she may suggest tests such as a Doppler Ultrasound. There is good evidence that compression stockings (light to medium) help to push blood back to your heart and so reduce aching. It's not known if they stop the varicose veins getting worse. You should wear them all day and moisturise your legs to prevent the skin cracking. Ideally they should be fitted properly – ask your GP about this.

Other treatments such as injections or surgery (stripping the veins) are usually only available on the NHS if your veins are really painful or have bled or caused other complications. The injections seal the vein, which then fades. Injections do have side-effects. There are newer treatments, including using a laser inside the vein to seal it – but this is not widely available.

When should I see my doctor?

You should see your doctor as soon as the veins become a nuisance. It's good to get your circulation checked and to make sure there is no treatable reason for your varicose veins.