Phlebitis is the inflammation of a venous blood vessel. Doctors also refer to phlebitis in the case of vein inflammation.
Phlebitis can occur in both superficial (directly under the skin) and deep veins. Venous inflammation often occurs in conjunction with thrombosis (blood clots). If phlebitis and a blood clot occur in a superficial vein, doctors call this thrombophlebitis. This is the most common form of phlebitis. However, it should be noted that thrombophlebitis rarely leads to bacterial inflammation.
Thrombophlebitis most commonly affects the superficial leg veins, in particular the great and small saphenous veins and their lateral branches. The trigger is usually varicose veins(varicose veins), in these cases it is also referred to as varicophlebitis.
However, the arm veins are also a typical location for phlebitis. However, this is usually preceded by blood sampling or a horizontal venous access for infusion therapy for various reasons. Very rarely, the veins in the chest or abdomen are inflamed.
In contrast to purulent inflammations and wound infections, which are caused by pathogens (especially bacteria), phlebitis is usually abacterial. This means that germs (bacteria) are not detectable as triggers.
Venous inflammation can becaused by
- Varicose veins
- Lack of exercise
- overweight
- Blood sampling
- Venous access for infusion therapy
- Smoking and contraceptive pills
- Increased blood clotting tendency
- fluid deficiency
- Tumor diseases
In summary, diseases that lead to
- an enlargement of the vein (varicose vein)
- a deterioration of the blood flow (thrombosis) or
- an injury to the vein (blood collection, infusion catheter)
are associated with an increased risk of phlebitis or thrombophlebitis.

Varicose veins can promote the development of phlebitis © hriana | AdobeStock
The cardinal signs of inflammation (redness, swelling, overheating, pain, functional impairment) also occur in thrombophlebitis.
External signs of thrombophlebitis are typically a painful, reddened strand in the course of the vein, sometimes also hardening and swelling. Fever may also occur.
The duration of phlebitis is usually a few days. In severe cases, the inflammation can also last for several weeks. A milder case is usually when the affected vein is not previously damaged. This is the case, for example, after infusion therapy via an indwelling venous catheter, where the inflammation subsides within a few days. However, if vein operations, thromboses and varicose veins cause such damage, the inflammation may well last longer.
Before an inflammation of the veins can be diagnosed, the doctor will carry out a thorough examination. He will ask about the patient's medical history. Important key points of this questioning are, for example, questions about known venous diseases such as varicose veins.
A physical examination is then carried out. As mentioned above, superficial phlebitis can often be seen with the naked eye. The affected vein is thick, hardened and causes pain when pressure is applied.
In a blood test, inflammation levels, particularly white blood cells, are often elevated.
A Doppler sonography - this ultrasound examination makes the blood flow visible - provides clarity. If the inflammation is located in a deep blood vessel, further examinations are necessary.
In more difficult cases, a computer or magnetic resonance imaging scan can also be arranged. However, this is only necessary in exceptional cases. In this context, it should be mentioned that vein inflammation without an obvious cause can also be an indication of a previously undetected tumor disease. In these cases, a tumor search must be carried out in addition to the examination and treatment of the phlebitis. The above-mentioned more complex examinations (such as computer tomography and magnetic resonance imaging) may be necessary.
It is important to have phlebitis treated in order to avoid secondary diseases. Phlebitis treatment depends on the type and severity of the phlebitis.
If the phlebitis is superficial, cooling and elevating the affected arm or leg will provide relief. An inserted venous catheter should also be removed. A compression bandage can support healing. If the pain is severe, the doctor will also recommend pain-relieving medication in the form of ointments or tablets.
In some cases of phlebitis in conjunction with a blood clot (thrombophlebitis), the doctor will remove the blood clot, especially if the pain is severe. To do this, he punctures the vein. In exceptional cases, it may also be necessary to administer an antibiotic if pus is released.
If the deep veins are also affected by the superficial phlebitis and thrombi have formed here, hospitalization may also be necessary. In particular, this should be arranged if there is a sudden onset of breathlessness that did not previously exist. The reason for this is that if the deep veins are involved, a clot (thrombus) can be carried into the lungs and lead to a so-called pulmonary embolism. Depending on the size of the thrombus, this then causes more or less pronounced shortness of breath.
It is not possible to prevent phlebitis with 100% certainty. However, there are some things you can do to keep your veins healthy.
You can reduce the risk of developing phlebitis by
- early treatment of varicose veins
- giving up smoking (this applies in particular to women who use hormonal contraception)
- Avoid sitting and standing for long periods, if this is not possible, do regular exercises for legs and feet
- Avoid wearing clothes that are too tight, especially those that constrict the legs
- drink enough to prevent the blood from thickening and reduce the risk of blood clots forming
- Do not leave venous catheters in the vessel for too long and
- Always inform the doctor of any changes to veins that have already been operated on
As a general rule, physical activity is the best prevention against phlebitis.
Exercise gets the blood circulation going and prevents many vein problems from developing in the first place.