What is PE?
A pulmonary embolism (PE) is a blood clot in one or more arteries of the lungs. Most PEs begin as blood clots in the deep veins of the legs or pelvis (deep vein thrombosis, or DVT). A portion of the clot can break off, travel through the bloodstream, and lodge in the lungs. Once a clot becomes lodged within the pulmonary arteries, it cannot travel elsewhere in the body. Anticoagulants are prescribed to prevent the existing clot from growing and to stop new clots from forming while your body gradually breaks down the clot naturally. PE is a serious condition, but with appropriate treatment, most patients recover well.
Common symptoms
- Sudden shortness of breath at rest or with mild exertion
- Chest pain that may worsen when you breathe deeply
- Rapid heartbeat (palpitations)
- Coughing, sometimes with blood-tinged mucus
- Feeling faint, lightheaded, or losing consciousness
- Leg swelling or pain if a DVT is also present
🚨 Seek emergency care immediately if you have:
- Call 911 or go to the nearest Emergency Department immediately for: sudden worsening shortness of breath, fainting or near-fainting, or severe chest pain
- Seek emergency care for: coughing up significant amounts of blood
- Seek emergency care for signs of major bleeding: vomiting blood, black or tar-like stools, bright red blood in stools, large amounts of blood in urine, or severe unexplained bruising
- If you strike your head while taking anticoagulants, seek medical assessment even if you initially feel well
- Contact your healthcare provider for: mild increase in symptoms, questions about your medication, unusual bleeding, or concerns about your recovery
Call 911 or go to the nearest Emergency Department.
Treatment
Treatment is typically 3–6 months for a first PE. Unprovoked PE or ongoing risk factors may require longer or indefinite therapy. Your specialist will guide this decision.
Trusted resources
Thrombosis Canada
thrombosiscanada.ca →Clot Connect
clotconnect.org →Contact your clinic
This information is for educational purposes only and does not replace personalized medical advice from your healthcare team.