Yes. A person can have more than one pulmonary embolism (PE), either because several clots block lung arteries during one episode or because a new clot causes another PE later. Having had a PE raises the chance of another, especially when clotting risks remain. Treatment and follow-up can lower that risk, and new sudden breathing trouble or chest pain needs emergency medical assessment.
How can someone have more than one pulmonary embolism?
A pulmonary embolism occurs when a blood clot blocks one or more arteries that carry blood through the lungs. The clot usually forms in a deep vein, often in the leg, breaks away, and travels through the bloodstream to the lungs.
There are two important ways to understand having more than one PE. First, a single episode can involve several clots or blockages in the lung arteries. Second, a person who has recovered from an earlier PE can develop a new clot that causes another episode. According to the American Heart Association, a PE can block one or more pulmonary arteries, and a history of PE increases the chance of having another.
A second PE does not necessarily mean that the first treatment was unsuccessful. The risk of new clots may continue after the original episode, particularly when an underlying health condition or another clotting risk factor remains. The reason for a repeat event can differ from person to person.
Why can a pulmonary embolism happen again?
The likelihood of another PE depends partly on what caused the first clot and whether the factors that encouraged clotting have resolved. A clot linked to a temporary event, such as major surgery, may carry a different long-term risk from one that occurs without a clear trigger or in the presence of an ongoing medical condition.
Factors associated with a greater chance of developing deep vein thrombosis (DVT) or PE include:
- A previous DVT or PE: A history of blood clots is itself an important risk factor.
- Ongoing medical conditions: Cancer, certain heart or lung conditions, and inflammatory diseases can increase clotting risk.
- Inherited clotting conditions or family history: Some people have a genetic tendency to develop blood clots.
- Reduced movement: Extended bed rest, hospitalization, recovery after surgery, or prolonged sitting can slow blood flow.
- Surgery, injuries, or fractures: These can damage blood vessels or limit movement during recovery.
- Hormonal factors: Estrogen-containing contraceptives, hormone replacement therapy, pregnancy, and the period after childbirth can increase clotting risk.
- Other factors: Older age and overweight or obesity are also associated with a greater risk of blood clots.
The Centers for Disease Control and Prevention (CDC) identifies these and other factors associated with DVT and PE. Having one or more risk factors does not mean that another PE will definitely occur. Healthcare professionals consider which factors apply, whether they are temporary or ongoing, and the circumstances of the previous clot.
How common is it to have another pulmonary embolism?
Repeat blood clots are a recognized concern after an episode of venous thromboembolism (VTE), the medical term that includes both DVT and PE. The CDC reports that about one-third of people who have had VTE experience a recurrence within 10 years. This figure covers both DVT and PE, rather than pulmonary embolism alone, and it does not predict an individual's personal risk.
The likelihood of recurrence varies with the original cause, ongoing risk factors, and the prevention plan recommended by a healthcare professional. A previous PE is a reason to discuss long-term prevention and follow-up, not a guarantee that another clot will develop.
What symptoms could occur with another PE?
A repeat pulmonary embolism can cause symptoms similar to those of the first episode. Symptoms may begin suddenly, although their nature and intensity can vary. Examples include:
- Sudden or unexplained shortness of breath
- Chest pain or discomfort that becomes worse when taking a deep breath or coughing
- A rapid or irregular heartbeat
- A cough, sometimes with blood in the mucus
- Lightheadedness, dizziness, or fainting
- Pain or swelling in one leg, which can occur with a deep vein blood clot
These symptoms can have causes other than PE, but a possible pulmonary embolism needs prompt medical assessment. The CDC's guidance on venous thromboembolism advises seeking immediate medical help for symptoms such as difficulty breathing, chest pain, coughing up blood, or faintness. If these symptoms develop suddenly or are concerning, call your local emergency number rather than waiting for them to improve.
Does ongoing shortness of breath mean the PE has returned?
Not necessarily. Some people continue to experience breathing difficulties or limitations in physical activity after a pulmonary embolism. These symptoms can have several explanations, including a lingering effect of the original event or another heart or lung problem. Their presence alone does not establish that a new clot has formed.
However, new or worsening breathlessness, chest pain, or a noticeable change from the usual recovery pattern needs medical assessment. The 2026 American Heart Association and American College of Cardiology guideline recommends checking for PE-related symptoms and activity limitations during follow-up for at least one year, including to identify chronic thromboembolic pulmonary disease or other causes of ongoing symptoms.
How do doctors check whether a second PE has occurred?
Healthcare professionals assess the current symptoms alongside the person's medical history, previous PE, recent illnesses or procedures, medicines, and other risk factors. They may perform a physical examination and order tests according to the clinical situation. Testing is important because symptoms alone cannot reliably distinguish a new PE from other conditions or lingering problems following the first event.
Possible tests include:
- Blood testing: A D-dimer test may help determine whether further testing is needed in an appropriate clinical setting.
- CT pulmonary angiography: This scan uses contrast material and CT imaging to show blood vessels in the lungs and look for a blockage.
- Ventilation-perfusion (V/Q) scan: This test examines air movement and blood flow in the lungs and may be used when CT pulmonary angiography is unsuitable.
- Ultrasound of the legs: This may be used to look for a DVT when a clot in the leg is suspected.
MedlinePlus, a service of the US National Library of Medicine, describes these approaches to evaluating pulmonary embolism. Not everyone needs every test. The healthcare team determines the appropriate investigations based on the person's symptoms, examination, history, and test results.
Can you have another PE while taking blood thinners?
Yes. Anticoagulants, commonly called blood thinners, lower the chance of new clots forming, but they do not eliminate the risk completely. A clot may occasionally develop despite treatment. If a PE is suspected while someone is taking an anticoagulant, urgent medical evaluation is necessary, and the treatment plan needs to be reviewed by the healthcare team.
Do not stop, increase, reduce, or switch an anticoagulant without medical guidance. If another clot is confirmed, clinicians investigate possible reasons for the event and determine whether the medicine, dose, or overall treatment approach needs to change. The decision depends on the specific medication, treatment history, clinical findings, and the balance between preventing clots and avoiding bleeding.
How is the risk of another pulmonary embolism reduced?
Preventing another PE usually involves addressing the factors that contributed to the first episode and following the recommended treatment plan. Depending on the circumstances, this may include:
- Taking anticoagulants as prescribed: Follow the prescribed schedule and discuss missed doses, side effects, or concerns with the prescribing professional.
- Reviewing treatment duration: Attend follow-up appointments to discuss whether anticoagulation should continue and when it may be safe to stop.
- Moving regularly: Avoid prolonged periods without movement when possible. During recovery from surgery or illness, follow the care team's advice about getting up and walking safely.
- Managing ongoing risks: Discuss cancer, chronic medical conditions, hormonal medicines, inherited clotting conditions, and personal or family history of blood clots with the healthcare team.
- Planning for higher-risk situations: Before surgery, hospitalization, or a period of restricted movement, tell healthcare professionals about the previous PE so they can assess whether preventive measures are needed.
The American Heart Association notes that many people receive anticoagulant treatment for three to six months, while those with recurrent PE or continuing risk factors may need treatment for longer. The optimal duration is individualized because anticoagulants can increase the risk of bleeding.
For adults whose PE occurred without a major reversible risk factor, or who have a persistent risk factor, the 2026 American Heart Association and American College of Cardiology guideline recommends continuing anticoagulation beyond the initial three-to-six-month treatment phase. The clinician must apply this guidance to the person's circumstances, including the risk of bleeding and other medical considerations.
What does having multiple pulmonary embolisms mean for recovery?
Having another PE can complicate recovery, but the outcome depends on factors such as how much the clot affects blood flow, the effect on the heart and lungs, other health conditions, and how promptly appropriate treatment is provided. The number of previous episodes alone cannot determine how a person will recover.
Some people recover well after treatment, while others may need longer-term anticoagulation or follow-up for continuing symptoms. Persistent shortness of breath or reduced ability to exercise should be discussed with a healthcare professional, even when there are no signs of an acute emergency. Regular follow-up helps the care team reassess symptoms, review medicines, and address the possibility of further clotting.
When should you seek emergency help?
If you have previously experienced a pulmonary embolism, seek emergency medical care for sudden or unexplained shortness of breath, new chest pain, coughing up blood, a rapid heartbeat with other concerning symptoms, or dizziness or fainting. Do not wait for a scheduled appointment or assume that prescribed blood thinners rule out a new clot. Prompt assessment is important because a pulmonary embolism can be life-threatening.
For symptoms that are persistent, unusual, or gradually worsening without signs of an immediate emergency, contact your healthcare professional promptly for advice. Explain your previous PE, when symptoms began, whether they have changed, and which medicines you take.