Venous thrombosis

Venous thrombosis is a blood clot that forms within a vein, most frequently in the legs.


Venous thrombosis is a blood clot that forms within a vein, most frequently in the legs. A swollen and painful leg, sometimes with a bluish discolouration is typical. Preventive measures include sufficient exercise, avoidance of excess weight and no smoking.


Main symptoms

  • Sudden appearance in a leg:
    • Throbbing pain
    • Overheating
    • Redness
    • Swelling
    • Bluish discolouration
    • Feeling of heaviness

Other symptoms

Causes and treatment


  • Damage to the vein wall
    • Inflammations
    • Injuries
  • Activation of coagulation
    • Often, a genetic predisposition (e.g. Factor V Leiden)
  • Slowing of blood flow
    • Lack of exercise
    • Confinement to bed
    • Travelling by air / bus
Risk factors

Further treatment by your doctor / in hospital

Possible tests
  • Ultrasound (sonography)
  • Blood test (search for blood clots)
Possible therapies
  • Operation to remove varicose veins
  • Blood-thinning medication (anticoagulation)
  • Medication to dissolve blood clots (thrombolysis)

What can I do myself?

  • Physical activity encourages blood flow and prevents varicose veins and thromboses
  • Wear support stockings
  • Sometimes rest with the legs up
  • Kneipp therapy
  • Stop smoking

Get a personal Preventive Care Recommendation now.

When to see a doctor?

  • A leg or arm swells up suddenly, is painful and turns blue
  • Persistent feeling of tightness in a leg or arm
  • Increasing breathlessness
  • Pain when breathing


Venous thrombosis

Exclusion of liability

CSS offers no guarantee for the accuracy and completeness of the information. The information published is no substitute for professional advice from a doctor or pharmacist.

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