Varicose veins can cause complications because they stop your blood flowing properly.

Most people who have varicose veins won't develop complications, but, if you do, it will usually be several years after your varicose veins first appear.

Some possible complications of varicose veins are explained below.

Bleeding

Varicose veins near the surface of your skin can sometimes bleed if you cut or bump your leg. The bleeding may be difficult to stop.

You should lie down, raise your leg and apply direct pressure to the wound. Seek immediate medical advice if this doesn't stop the bleeding.

Blood clots

If blood clots form in superficial veins (veins located just under the surface of your skin), it could lead to conditions such as thrombophlebitis or deep vein thrombosis.

Thrombophlebitis

Thrombophlebitis is swelling (inflammation) of the veins in your leg caused by blood clots forming in the vein. This can occur within your varicose veins and can:

• be painful
• look red
• feel warm

When thrombophlebitis occurs in one of the superficial veins in your leg it's known as superficial thrombophlebitis.

Like varicose veins, thrombophlebitis can be treated with compression stockings. In some cases, non-steroidal anti-inflammatories (NSAIDs), such as ibuprofen, may be prescribed.

Deep vein thrombosis

Deep vein thrombosis may develop in up to 20% of people who develop a blood clot in superficial veins.

It can cause pain and swelling in the leg, and may lead to serious complications such as pulmonary embolism.

Chronic venous insufficiency

If the blood in your veins doesn't flow properly, it can interfere with the way your skin exchanges oxygen, nutrients and waste products with your blood.

If the exchange is disrupted over a long period of time, it's known as chronic venous insufficiency.

Chronic venous insufficiency can sometimes cause other conditions to develop, including those described below.

Varicose eczema

Varicose eczema is a condition that causes your skin to become red, scaly and flaky. You may also develop blisters and crusting of your skin.

This condition is often permanent, but does not lead to any major problems.

Lipodermatosclerosis

Lipodermatosclerosis causes your skin to become hardened and tight, and you may find it turns a red or brown colour. The condition usually affects the calf area.

Venous ulcers

A venous ulcer develops when there is increased pressure in the veins of your lower leg. This causes fluid to seep from your vein and collect under the skin.

The fluid can cause the skin to thicken, swell and eventually break down to form an ulcer. Venous ulcers most commonly form in the ankle area.

You should see your GP immediately if you notice any unusual changes in your skin, such as those mentioned above. These conditions can usually be easily treated, but it's important you receive treatment as soon as possible.

Read more about venous leg ulcers.