Phlebitis is the inflammation of a vein. It often occurs in the legs but can affect veins in other parts of your body, as well. It may be caused by damage to the vein wall or by a blood clot that blocks a vein.

Phlebitis may be caused by damage to the vein wall or by a blood clot that blocks a vein. Inflammation caused by a blood clot, or thrombus, is called thrombophlebitis.

Blood clots can occur in veins near the surface of the skin or in veins deep within your muscles. If a blood clot is in a deep vein, it’s called deep vein thrombophlebitis or deep vein thrombosis (DVT).

Illustration of red streaking on skin of leg, indicating blood clotShare on Pinterest
Illustration by Sophia Smith

Phlebitis can affect both superficial and deep veins.

Superficial phlebitis refers to the inflammation of a vein near the surface of your skin. It can result from a blood clot or from something causing irritation in a vein, such as an intravenous (IV) catheter.

This type of phlebitis usually isn’t serious, but it can lead to:

  • infection of the surrounding skin
  • wounds on the skin
  • bloodstream infections

If a clot in the superficial vein is extensive enough and involves the area where the superficial vein and a deep vein come together, a DVT can develop.

Deep vein phlebitis refers to inflammation of a deeper, larger vein, such as those found in your legs. Deep vein phlebitis is more likely to be caused by a blood clot, which can have very serious consequences.

A blood clot may break off and travel to your lungs. This is called a pulmonary embolism (PE) and can be life threatening. It’s important to know the risk factors and symptoms of a DVT so you can seek prompt attention from a healthcare professional.

Symptoms of phlebitis affect the arm or leg where the inflamed vein is located. They often include swelling and pain in the affected area. These symptoms can vary depending on whether you have superficial or deep vein phlebitis.

Superficial phlebitis symptoms

If the inflamed vein is located near the surface of your skin, you may experience:

  • redness
  • swelling
  • warmth
  • tenderness
  • visible red “streaking“ on the skin along the vein
  • a rope- or cord-like structure that you can feel through the skin

Deep vein phlebitis symptoms

If the inflamed vein is deep within a muscle, you may experience the following symptoms in the affected limb:

  • pain
  • swelling
  • warmth
  • skin discoloration

You may also notice pain in your calf or thigh if your phlebitis is caused by a DVT. The pain may be more noticeable when walking or flexing your foot.

Only about half of those who develop a DVT experience symptoms, according to the Centers for Disease Control and Prevention (CDC). This is why a DVT may not be diagnosed until a serious complication occurs, such as a PE.

Symptoms of PE include:

Call your local emergency services if you think you may be experiencing a PE. This is a medical emergency that requires immediate treatment.

The most common causes of phlebitis are injury or irritation to the lining of a blood vessel or a blood clot inside the vein. In the case of superficial phlebitis, this may be due to:

  • placement of an IV catheter
  • administration of irritating medications into your veins
  • a small clot
  • an infection
  • a soft tissue injury

Causes of deep vein phlebitis may include:

  • irritation or injury due to physical trauma, such as surgery, a broken bone, or serious injury
  • slowed blood flow due to lack of motion, which may occur if you’re on bed rest or sitting in one position for a long period of time
  • blood that is more likely to clot, which may be due to medications, cancer, connective tissue disorders, or inherited blood clotting conditions

A number of factors can increase your risk of phlebitis. You may be more likely to experience phlebitis if you:

  • have a personal or family history of blood clots
  • have a blood clotting disorder, such as factor V Leiden thrombophilia
  • take hormone therapy or birth control pills
  • experience long periods of inactivity, which may be needed after surgery
  • sit for long periods of time, such as during travel
  • have certain cancers and cancer treatments
  • are pregnant
  • have overweight or obesity
  • smoke
  • misuse alcohol
  • have varicose veins, which can increase your risk of superficial phlebitis
  • are over age 60

A doctor can often diagnose phlebitis based on your symptoms and a physical exam. You may not need any special tests.

However, if a blood clot is suspected as the cause of your phlebitis, your doctor could perform several tests in addition to taking your medical history and examining you. These tests may include:

  • Ultrasound. An ultrasound uses sound waves to show the flow of blood through your veins and arteries. It can be used to detect blockages or blood clots in the deep veins of the affected limb.
  • D-dimer blood test. This test measures levels of d-dimer, a substance that’s released when a clot breaks up. If your d-dimer test is negative, you likely don’t have a clot.
  • Venography. Your doctor performs a venogram by injecting a special dye into a vein in your foot. An X-ray is then taken as the dye flows up your leg. This allows your doctor to see the deep veins in your leg and check for the presence of a blood clot.
  • Imaging tests. Your doctor may perform an MRI scan or CT scan to help determine if a blood clot is present in your veins.

If a clot is detected, your doctor may want to take blood samples to test for blood clotting disorders that could have caused it.

Treatment for phlebitis may involve both self-care and medical treatment. Your treatment options may depend on whether you have superficial or deep vein phlebitis.

Self-care at home

There are steps you can take at home to help reduce the pain and swelling of phlebitis. These include:

  • applying a warm compress to the affected area
  • keeping your leg raised while resting
  • taking nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen. (If you also take a blood thinner, do not take NSAIDs unless prescribed by your doctor).

Medical treatment

Superficial phlebitis often improves within a few weeks using self-care measures. If phlebitis affects a deep vein or you’re at risk of developing DVT, your doctor may recommend additional treatments. These may include:

  • Anticoagulant blood-thinning medications. Anticoagulants reduce your blood’s ability to clot. This can help prevent an existing clot from becoming larger and reduce the risk of additional clots. These medications can be injected or taken orally.
  • Thrombolytic medications. Also called “clot busters,“ thrombolytics dissolve a clot. They’re typically used for more serious cases of DVT.
  • Varicose vein treatment. If you have recurrent superficial phlebitis in varicose veins, your doctor may recommend treatment for your varicose veins. Options may include sclerotherapy, laser treatment, or surgical removal of varicose veins.
  • Thrombectomy. This procedure may be performed if the DVT is very extensive and causes significant problems with blood return in your limb. A surgeon inserts a wire and catheter into the affected vein and either removes the clot, dissolves it with medications that break up the clot, such as tissue plasminogen activators, or performs a combination of both.
  • Vena cava filter. Insertion of a filter into one of your major blood vessels, the vena cava, may be recommended if you have a DVT and are at high risk of a PE but can’t take blood thinners. This filter won’t prevent blood clots from forming, but it will prevent pieces of the clot from traveling to your lungs.

Vena cava filters are typically removable because permanent filters can cause complications after being in place for 1 to 2 years. These complications can include:

  • infection
  • life threatening damage to the vena cava
  • enlargement of blood vessels around the filter, which allows clots to pass by the filter and into the lungs
  • clots up to, on, or past the filter within the vena cava, the latter of which can break off and travel into the lungs

Minimizing your risk factors for developing future DVTs will also be an important part of treatment. Some key prevention strategies include:

  • discussing your risk factors with your doctor, especially before a surgical procedure
  • getting up and walking as soon as possible after surgery
  • avoiding a sedentary (inactive) lifestyle
  • wearing compression socks
  • stretching your legs and drinking plenty of water when traveling
  • talking with your doctor about a smoking cessation program, if you smoke
  • maintaining a moderate weight
  • taking medications as instructed by your doctor, which may include blood thinners

Phlebitis is inflammation of a vein, caused by a blood clot or damage to the vein wall. Superficial phlebitis affects veins close to the surface of your skin. Deep vein phlebitis affects veins deep within your muscles.

Symptoms of phlebitis may include redness, pain, and swelling in the affected area. Self-care strategies such as applying a warm compress, keeping your leg raised while resting, and taking NSAIDs can help relieve these symptoms. Treatment options for phlebitis include anticoagulant medications or surgical removal of blood clots.

Superficial phlebitis often heals without lasting effects.

DVT, on the other hand, can be life threatening and requires immediate medical attention. It’s important to know if you have risk factors for developing a DVT and to receive regular medical attention from a doctor.

If you’ve experienced a DVT before, you may be more prone to experiencing another in the future. Taking proactive steps may help prevent DVT.