Superficial Thrombophlebitis

What is thrombophlebitis?

• Phlebitis means inflammation of a vein.
• Thrombo(sis) means a blood clot in a vein.

A vein is a blood vessel that takes blood towards the heart. If a vein becomes inflamed, a blood clot commonly forms inside the inflamed portion. So, the term thrombophlebitis is used to mean an inflamed vein, with or without a small blood clot inside the vein. (Thrombophlebitis is commonly just called phlebitis.)

What is superficial thrombophlebitis?

The superficial veins are the ones that you can often see or feel just under the skin. Most bouts of superficial thrombophlebitis occur in a leg vein, but any superficial vein can be affected. A typical site is in a varicose vein in a leg. Varicose veins are common, particularly in pregnant women. Superficial thrombophlebitis is not usually serious, but complications can sometimes occur (see below).

Note: this leaflet does not deal with inflammation or thrombosis of deep veins. The deep veins are larger, pass through the muscles in your arms and legs, and you cannot see or feel them. Some people get confused between superficial thrombophlebitis and deep vein thrombosis. They are quite different. A deep vein thrombosis (DVT) is more serious. See separate leaflet called 'Deep Vein Thrombosis (DVT)' for more detail.

What causes superficial thrombophlebitis?

Many cases occur for no apparent reason. A slight injury to the vein may trigger the inflammation in some cases.

Risk factors

There are a number of 'risk factors' that make it more likely for inflammation or a blood clot to develop in a vein, which may lead to superficial thrombophlebitis.

• Varicose veins - Many cases occur in people who have varicose veins of the legs. Varicose veins are prone to minor injuries which can lead to inflammation.
• Intravenous injection or cannulation - Sometimes it occurs after having intravenous injections (injections into the veins) or intravenous infusions ('drips') in hospital. These are commonly given in hand or arm veins. Such procedures can injure the vein and may trigger inflammation. Damage to the veins in this way is also common in people who inject 'street drugs'.
• Previous problems with veins - If someone has had previous superficial thrombophlebitis or a previous deep vein thrombosis, they are more likely to get superficial thrombophlebitis.
• Abnormalities of blood clotting factors - Various conditions can alter certain chemicals ('clotting factors') in the bloodstream, which make the blood clot more easily. These include: using the oral contraceptive pill, using hormone replacement therapy, cancer, smoking, and pregnancy. There are also some less common hereditary blood disorders where blood clots develop more readily than usual.
• Stasis of blood (blood flowing more slowly than normal) - For example, this occurs in veins that are varicose, during long flights, in people who are immobile, and also following major surgery.

What are the symptoms of superficial thrombophlebitis?

Swelling, redness, and tenderness along a part of the vein are the usual symptoms. You may develop a fever (high temperature). If a blood clot develops inside the inflamed part of the vein, the vein may then feel hard or 'knobbly'. The blood clot is usually of little concern as it is small. There are other veins which carry the blood, and bypass the blocked vein.

When the inflammation settles, a persistent darker area of skin (hyperpigmentation) may remain over the affected vein. A persistent firm nodule (small lump) may also remain below the skin at the site of the affected vein. This may be tender to the touch for some time.

Do I need any investigations?

Your doctor is usually able to diagnose superficial thrombophlebitis by talking to you and examining the affected area. Investigations are not usually needed, especially if you have one of the risk factors for superficial thrombophlebitis (see above). However, if your doctor is concerned that you may have a deep vein thrombosis (see below), they may advise that you have some tests to exclude this. This usually means a special ultrasound scan of the affected area to look for any clots in the deep veins.

If you have recurrent bouts of thrombophlebitis, especially if you have no real risk factors for superficial thrombophlebitis, your doctor may suggest some tests to check that you do not have any problems with the clotting of your blood. They may also suggest other tests to look for more rare causes of recurrent superficial thrombophlebitis (see below).

What is the treatment for superficial thrombophlebitis?

Most bouts of superficial thrombophlebitis settle within 2-6 weeks. No treatment may be needed if the symptoms are mild. Treatment aims to ease symptoms. The following treatments may be helpful:

• Keep active. Try to keep up with normal activities as much as possible.
• A hot flannel (cloth) placed over the vein. This may ease the pain.
• Painkilling tablets. Anti-inflammatory painkillers such as ibuprofen may ease the pain (but are not advised if you are pregnant). Paracetamol is an alternative. Some people may not be able to take anti-inflammatory painkillers. Check with your doctor or pharmacist. Always read the packet leaflet that explains possible side-effects. See separate leaflet called 'Anti-inflammatory Painkillers' for more detail. (There is also some limited evidence that anti-inflammatory painkillers taken by mouth may reduce the risk of superficial thrombophlebitis enlarging or extending within a vein and/or it coming back. However, more studies are needed to confirm this.)
• Anti-inflammatory creams or gels. An example is ibuprofen gel. These are an alternative if superficial thrombophlebitis is mild and only affects a small area of vein. They tend to produce fewer side-effects than those taken by mouth.
• Raising the affected leg. When you rest (when watching TV, or reading a book, etc), if you raise an affected leg so that your foot is higher than your hip, it helps to reduce swelling and discomfort. You can do this by lying on a sofa and putting the leg up on some cushions. When sleeping in bed, you can keep your leg raised by putting it on a pillow.
• Compression (support) stockings. These may be advised by your doctor if a vein in your leg is affected. They may ease discomfort and reduce swelling whilst the inflammation settles.

If varicose veins are the source of the problem, once the inflammation has settled, you may wish to consider treatment to remove the varicose veins. See your doctor for advice. There is another leaflet that discusses varicose veins in more detail.

If your doctor feels that you may have a deep vein thrombosis or be at high risk of developing one, they may suggest that you are referred either to the hospital or to a special 'DVT clinic' so that you can have any investigations necessary (see above), as well as any treatment. Sometimes, prophylactic (or 'just in case') treatment may be given to people who have superficial thrombophlebitis and may be at high risk of developing a DVT. This involves injection of a drug to thin the blood.

Are there any complications from superficial thrombophlebitis?

The inflammation and pain usually settle within a few weeks. Most people make a full recovery. The possible complications listed below are uncommon, but are listed to give a guide as to 'what to look out for'. See a doctor as soon as possible if you suspect that a complication is developing.

Infection

Sometimes the affected vein becomes infected. The pain may then become worse, and the redness spreads. You are likely to feel generally unwell. Infection is more common in someone who has had an intravenous cannula ('a drip') inserted for a long period, in people who abuse 'street drugs' or in people with a weakened immune system. Antibiotics are needed to treat the infection. If the infection is severe, you may need to be admitted to hospital for intravenous antibiotics (antibiotics given directly into a vein). Rarely, infection in a vein becomes severe and may spread to other areas of the body.

Blood clot extension

In some cases, the blood clot can extend further up the vein. If the clot extends to where the superficial vein and the deep, larger veins join, a 'deep vein thrombosis' (DVT) can develop. This is more likely if the superficial thrombophlebitis is in the upper thigh or the groin, near to where the superficial veins and the deep veins of the leg meet. There is a similar meeting point of superficial and deep veins at the crease behind the knee. It is also more likely to occur if superficial thrombophlebitis develops in a previously normal vein (not a varicose vein), if you have had a DVT before, or if you are immobile for some reason.

Another leaflet deals with DVT. Very briefly, see a doctor urgently if:

• Inflammation, redness, or hardness spreads up your inner thigh towards your groin or is around the back of your knee or calf.
• Your whole leg swells.
• Pain becomes suddenly worse.
• You develop any new breathing problems, or get chest pains. (Sometimes a clot from a DVT breaks off and travels to the lung.)

Recurrent superficial thrombophlebitis

It is common for people with varicose veins to get recurring bouts of superficial thrombophlebitis. However, in some people with recurring bouts of superficial thrombophlebitis, it may be the first indication of a more serious condition. This is especially if the bouts are occurring at different sites, and in different veins in someone without varicose veins.

Tests may be advised if there is no explanation for recurring bouts of superficial thrombophlebitis. Rarely, recurring bouts of superficial thrombophlebitis can be a sign of a cancer within the body. It may also be a sign of other rare conditions including polyarteritis nodosa (a rare condition of unknown cause where there is patchy inflammation of the walls of the arteries).