Blood Clots (DVT & Pulmonary Embolism)
Understanding venous thromboembolism — causes, treatment and prevention
A blood clot that forms in a deep vein — most often in the leg — is called a deep vein thrombosis (DVT). If part of that clot breaks off and travels to the lungs, it becomes a pulmonary embolism (PE), which can be life-threatening. Together, DVT and PE are known as venous thromboembolism (VTE). Around 60,000 people in the UK are affected by VTE each year.
What causes blood clots?
Blood clots are more likely to form when blood flows slowly, when the walls of blood vessels are damaged, or when the blood is more prone to clotting than normal. Common risk factors include prolonged immobility (long-haul flights, bedrest after surgery), pregnancy, taking the combined oral contraceptive pill or hormone replacement therapy, cancer, obesity, dehydration and certain inherited conditions that make the blood clot more easily.
Symptoms of DVT and PE
A DVT typically causes pain, swelling, redness and warmth in one leg — usually the calf. A PE can cause sudden breathlessness, chest pain that worsens with deep breathing, coughing (sometimes with blood), and rapid heart rate. A massive PE can cause collapse and is a medical emergency. Not all DVTs cause obvious symptoms, which is why they are sometimes only detected after a PE has occurred.
How are blood clots treated?
Blood clots are treated with anticoagulant medicines — commonly called blood thinners — which prevent the clot from growing and new clots from forming. The body gradually dissolves the existing clot over time. Modern direct oral anticoagulants (DOACs) — such as rivaroxaban and apixaban — are tablet form, easy to take, and require no routine blood monitoring. Most people with a DVT or PE are treated for at least three to six months.
Preventing blood clots
There are several effective ways to reduce the risk of blood clots. During long journeys, taking regular breaks to walk around, staying well hydrated and doing leg exercises in your seat all help. After surgery, your hospital team will prescribe blood-thinning injections and compression stockings to reduce VTE risk. If you are at high risk due to a medical condition, your GP may recommend long-term anticoagulation.
Living on anticoagulant treatment
Anticoagulants are highly effective but require some awareness of bleeding risk. You should avoid taking anti-inflammatory painkillers (such as ibuprofen or naproxen) alongside anticoagulants unless specifically prescribed. Always carry your anticoagulant alert card and tell any healthcare professional — including your dentist — that you are taking blood thinners before any procedure. Information in this article has been prepared following careful evaluation of current national guidelines on venous thromboembolism.