--- title: "Pulmonary embolism: Symptoms & Treatment | HealthAnswers" description: "Pulmonary embolism — blood clot in the lung, symptoms including breathlessness and chest pain, emergency treatment, and NHS prevention of recurrence." url: https://healthanswers.co.uk/conditions/pulmonary-embolism/ robots: noindex --- # Pulmonary embolism: Symptoms & Treatment | HealthAnswers Health A–Z Pulmonary embolism — blood clot in the lung, symptoms including breathlessness and chest pain, emergency treatment, and NHS prevention of recurrence. Written by HealthAnswers editorial team Medically reviewed by [HealthAnswers UK doctor review panel](https://healthanswers.co.uk/our-doctors/) Reviewed 3 July 2026 ## Quick answer What is pulmonary embolism? A pulmonary embolism (PE) is a blockage in a blood vessel in the lung, usually caused by a blood clot that has travelled from a deep vein in the leg (deep vein thrombosis). It is a medical emergency. Symptoms include sudden breathlessness, chest pain worse on breathing in, coughing up blood, and a rapid heartbeat. Call 999 if you suspect a PE. Treatment is anticoagulation — blood-thinning medicines — to stop clots growing and new clots forming. ## Who is this page for? This page is for people in the UK who want a plain-English overview of Pulmonary embolism, including when to seek help and what NHS care usually involves. It explains general information, not what is wrong with you personally. ## Who should skip this page? Skip this page if you need a diagnosis, a prescription, or emergency care. It cannot replace a GP, pharmacist, NHS 111 or 999. If you are in immediate danger, call 999; for urgent advice that is not life-threatening, call 111 in England, Scotland or Wales, or use your GP out-of-hours service in Northern Ireland. On this page 7 sections ## Key facts about pulmonary embolism - Pulmonary embolism is usually caused by a clot travelling from a leg vein (DVT) — together called venous thromboembolism (VTE). - Sudden breathlessness and pleuritic chest pain (worse on breathing in) are hallmark symptoms. - Risk increases after surgery, prolonged immobility, pregnancy, cancer, and with the combined contraceptive pill. - Diagnosis uses clinical scoring, D-dimer blood test, and CT pulmonary angiogram. - Anticoagulation for at least 3 months is standard — longer if risk factors persist. ## Pulmonary embolism — a clot in the lung A **pulmonary embolism (PE)** is a **blockage in a lung artery**, usually caused by a **blood clot** that has travelled from elsewhere in the body — most often a **deep vein thrombosis (DVT)** in the leg. Together, DVT and PE are called **venous thromboembolism (VTE)**. PE is a **medical emergency**. Large clots can **stop blood flow to the lungs**, strain the heart, and be **fatal without prompt treatment**. ## Symptoms — act fast **Call 999** if you or someone else has: - Sudden breathlessness — may come on rapidly - Chest pain — sharp, worse on breathing in (pleuritic) - Coughing up blood - Rapid or irregular heartbeat - Fainting or feeling lightheaded - Anxiety or a sense of impending doom Symptoms vary — a **small PE** may cause mild breathlessness, while a **massive PE** causes **collapse**. ## Risk factors - Recent surgery — especially hip, knee, or abdominal - Prolonged immobility — long flights, hospital bed rest, leg plaster - Cancer and chemotherapy - Pregnancy and the first 6 weeks after birth - Combined contraceptive pill and HRT - Previous DVT or PE - Obesity - Thrombophilia — inherited clotting disorders ## Diagnosis - Clinical assessment — Wells score estimates probability - D-dimer blood test — elevated in active clotting; normal result helps exclude PE in low-risk patients - CT pulmonary angiogram (CTPA) — gold-standard imaging - Leg ultrasound — finds DVT in many cases - ECG and blood gases — assess heart strain and oxygen levels ## Treatment **Anticoagulation** — blood-thinning medicines prevent clots enlarging and new clots forming: - DOACs — apixaban, rivaroxaban, edoxaban, dabigatran — often started immediately - Heparin then warfarin — alternative pathway **Severe PE** with low blood pressure (massive PE): - Thrombolysis — clot-busting drugs such as alteplase - Surgical or catheter embolectomy — rare, selected cases **Supportive care** — oxygen, fluids, monitoring on a hospital ward or HDU. ## Duration of treatment **Provoked PE** (clear trigger — surgery, immobility) — anticoagulation for **at least 3 months**. **Unprovoked PE** — often **6 months or longer**; some patients need **lifelong** anticoagulation based on bleeding versus clot risk. ## Prevention - Move regularly on long journeys — walk every 2 to 3 hours - Compression stockings during and after surgery - Prophylactic anticoagulation during hospital admission when at risk - Treat DVT early before clots embolise See [deep vein thrombosis](https://healthanswers.co.uk/conditions/deep-vein-thrombosis/) for leg clot symptoms and [shortness of breath](https://healthanswers.co.uk/symptoms/shortness-of-breath/) when breathlessness has other causes. ## ! When to see a GP about pulmonary embolism Call **999** immediately for sudden breathlessness, chest pain that is sharp and worse when breathing in, coughing up blood, fainting, or a rapid heartbeat — especially after recent surgery, a long flight, leg injury, or if you have cancer or are pregnant. These may indicate a pulmonary embolism. See a GP promptly for unexplained leg swelling, pain, or warmth on one side — possible DVT before a clot reaches the lungs. If already on anticoagulation, seek urgent help for new breathlessness or significant bleeding. ## Common questions about pulmonary embolism What causes a pulmonary embolism? Most pulmonary emboli are blood clots that form in a deep leg vein (DVT) and break off, travelling through the heart to lodge in lung arteries. Less commonly, clots form in the pelvis, arm veins, or right side of the heart. Fat, air, or tumour fragments can rarely cause embolism. What are the symptoms of a pulmonary embolism? Sudden breathlessness — sometimes severe — is the most common symptom. Other signs include sharp chest pain worse on deep breathing, rapid heartbeat, coughing (sometimes blood), feeling faint, and anxiety. Large PEs cause collapse and cardiac arrest. Small PEs may cause milder symptoms. How is a pulmonary embolism diagnosed? Doctors assess clinical probability using Wells score. A D-dimer blood test helps rule out PE in low-risk patients. CT pulmonary angiogram (CTPA) is the main imaging test — shows clots in lung arteries. Leg ultrasound may find an associated DVT. ECG and blood gases support assessment. How is pulmonary embolism treated? Anticoagulation — blood-thinning medicines — is the main treatment. Options include apixaban, rivaroxaban, edoxaban, dabigatran, or heparin followed by warfarin. Severe PE with low blood pressure may need thrombolysis (clot-busting drugs) or surgical embolectomy. Oxygen and supportive care are given as needed. How long do I take blood thinners after a PE? At least 3 months for a first provoked PE (clear trigger such as surgery). Unprovoked PE or ongoing risk factors may need longer — sometimes lifelong anticoagulation. Your doctor balances clot risk against bleeding risk. Can I prevent pulmonary embolism? Move regularly on long journeys — walk and flex ankles. Stay hydrated. After surgery or during hospital admission, you may receive compression stockings and anticoagulant injections. Treat DVT promptly. Discuss clot risk with your doctor if pregnant, on hormone therapy, or having cancer treatment. What is the outlook after a pulmonary embolism? Most people recover well with treatment. A large PE can be life-threatening — early treatment saves lives. Some people develop chronic thromboembolic pulmonary hypertension (CTEPH) — breathlessness persisting months later — which needs specialist assessment. ## Sources - [NHS — Pulmonary embolism](https://www.nhs.uk/conditions/pulmonary-embolism/) - [NICE — Venous thromboembolic diseases](https://www.nice.org.uk/guidance/ng158) - [NHS — Deep vein thrombosis (DVT)](https://www.nhs.uk/conditions/deep-vein-thrombosis-dvt/)