9 Critical Pulmonary Embolism Symptoms You Should Never Ignore

A pulmonary embolism (PE) is a serious and potentially life-threatening condition that occurs when a blood clot blocks one or more arteries in the lungs. Most commonly, these blood clots travel from the legs or other parts of the body to the lungs, where they obstruct blood flow and prevent oxygen from reaching lung tissue. Understanding the symptoms of pulmonary embolism is crucial because early detection and prompt medical treatment can be lifesaving.

Pulmonary embolism affects approximately 900,000 people in the United States each year and can be fatal if not treated quickly. The condition can range from mild to severe depending on the size of the clot, the number of clots, and the portion of the lung affected. While some people may experience obvious and severe symptoms, others may have subtle signs that are easy to overlook. This makes awareness of all possible symptoms essential for everyone, especially those at higher risk.

In this comprehensive guide, we’ll explore the nine critical symptoms of pulmonary embolism that you should never ignore, along with information about causes, risk factors, and prevention strategies.

1. Sudden Shortness of Breath

Sudden, unexplained shortness of breath is often the first and most common symptom of a pulmonary embolism. This breathlessness typically appears without warning and may occur whether you’re active or at rest.

The shortness of breath happens because the blood clot blocks blood flow to a portion of the lung, preventing that area from receiving oxygen and functioning properly. As a result, your body cannot get enough oxygen, and you feel like you cannot catch your breath no matter how hard you try.

Key characteristics of PE-related shortness of breath:

• Sudden onset without an obvious trigger
• Worsens with physical activity or exertion
• May be accompanied by a feeling of anxiety or panic
• Does not improve with rest
• May progressively worsen over time

Unlike shortness of breath from exercise or mild respiratory infections, PE-related breathlessness feels disproportionate to your activity level and can be frightening in its intensity. If you experience sudden, severe shortness of breath, especially combined with other symptoms on this list, seek emergency medical attention immediately.

2. Sharp Chest Pain

Chest pain is another hallmark symptom of pulmonary embolism and is reported by approximately 50% of patients with PE. The pain is typically sharp and stabbing, and it often worsens when you take a deep breath, cough, eat, or bend over.

This type of chest pain, called pleuritic chest pain, occurs because the blood clot causes inflammation of the pleura—the membrane surrounding the lungs. When you breathe deeply, the inflamed pleura rubs together, causing sharp pain.

Distinguishing features of PE chest pain:

• Sharp, stabbing sensation rather than pressure or squeezing
• Located on one side of the chest or under the breastbone
• Intensifies with deep breathing (pleuritic pain)
• May radiate to the shoulder, arm, neck, or jaw
• Can be mistaken for a heart attack or muscle strain

It’s important to note that chest pain from a pulmonary embolism can sometimes mimic a heart attack. Both conditions are medical emergencies, so any new or severe chest pain warrants immediate evaluation by healthcare professionals.

3. Rapid or Irregular Heart Rate

A rapid heartbeat, medically known as tachycardia, is a common response to pulmonary embolism. When a blood clot blocks blood flow in the lungs, your heart must work harder to pump blood through the remaining open vessels and to compensate for reduced oxygen levels in the blood.

Your heart rate may increase to 100 beats per minute or higher while at rest. Some people also experience palpitations—the sensation that your heart is racing, pounding, or beating irregularly.

Heart-related symptoms in pulmonary embolism:

• Resting heart rate above 100 beats per minute
• Sensation of heart racing or pounding
• Irregular heartbeat or skipped beats
• Feeling your heartbeat in your chest, throat, or neck
• Heart rate that doesn’t return to normal with rest

A rapid heart rate combined with other symptoms like shortness of breath and chest pain strongly suggests a pulmonary embolism. The strain on the heart can be dangerous, potentially leading to heart failure if the clot is large or if multiple clots are present.

4. Cough (Sometimes with Bloody Sputum)

A persistent cough is another symptom that may indicate a pulmonary embolism. The cough may be dry or may produce mucus. In more serious cases, you might cough up blood or blood-streaked mucus, a condition called hemoptysis.

Coughing occurs because the blood clot causes irritation and inflammation in the lung tissue. When a section of the lung is deprived of blood flow, it can become damaged, leading to bleeding within the lung that may be expelled through coughing.

Cough characteristics in PE:

• New cough that appears suddenly
• Persistent cough that doesn’t respond to typical remedies
• Dry cough or cough with mucus production
• Blood-tinged sputum or frank blood (hemoptysis)
• Cough that worsens with deep breathing

While not everyone with a pulmonary embolism will cough up blood, this symptom is particularly concerning and requires immediate medical evaluation. Hemoptysis can range from small streaks of blood in the mucus to more significant amounts of bright red blood.

5. Lightheadedness or Dizziness

Feeling lightheaded, dizzy, or faint is a symptom that occurs when the pulmonary embolism is significant enough to reduce blood oxygen levels and blood pressure. When your lungs cannot oxygenate blood properly due to blocked blood vessels, your brain and other organs don’t receive adequate oxygen.

This symptom can range from mild lightheadedness to severe dizziness that makes it difficult to stand or walk. In extreme cases, pulmonary embolism can cause fainting (syncope), which indicates a severe, life-threatening blockage.

Signs of lightheadedness related to PE:

• Feeling unsteady or off-balance
• Sensation that the room is spinning
• Weakness or feeling like you might faint
• Difficulty concentrating or confusion
• Brief loss of consciousness

Fainting or near-fainting episodes in the context of pulmonary embolism indicate that the clot is significantly affecting your cardiovascular system. This is considered a medical emergency requiring immediate hospitalization, as it suggests the heart is struggling to maintain adequate blood pressure and circulation.

6. Leg Pain or Swelling

Since most pulmonary embolisms originate from blood clots in the legs (deep vein thrombosis or DVT), you may experience symptoms in your lower extremities before or along with lung symptoms. Leg pain and swelling occur when a blood clot forms in the deep veins of the leg, blocking blood flow and causing fluid buildup.

The pain is often described as a cramping or aching sensation, typically in the calf, but it can also affect the thigh. The affected leg may appear swollen, red, and feel warm to the touch compared to the other leg.

DVT symptoms that may precede or accompany PE:

• Swelling in one leg (rarely both legs)
• Pain or tenderness in the calf or thigh
• Warmth in the affected area
• Red or discolored skin on the leg
• Visible enlarged veins
• Pain that worsens when walking or standing

Not everyone with a pulmonary embolism will have noticeable leg symptoms, as the clot may have already traveled to the lungs or may have formed in a location other than the legs. However, if you notice leg symptoms combined with breathing difficulties or chest pain, it strongly suggests the possibility of DVT with pulmonary embolism.

7. Excessive Sweating

Sudden, excessive sweating or clamminess is a symptom that can occur with pulmonary embolism, particularly when the blockage is severe. This symptom results from your body’s stress response as it struggles to maintain adequate oxygen levels and blood pressure.

The sweating associated with PE is often described as “cold sweats”—you may feel clammy and cold despite sweating profusely. This is different from sweating due to exercise or warm temperatures, as it occurs regardless of environmental conditions and is often accompanied by other distressing symptoms.

Characteristics of PE-related sweating:

• Sudden onset of profuse sweating
• Cold, clammy skin
• Sweating that seems excessive for the situation
• May be accompanied by pale or bluish skin color
• Often occurs with other symptoms like chest pain or shortness of breath

Excessive sweating, especially when combined with other cardiovascular symptoms, indicates that your body is under significant stress. This autonomic response is your nervous system’s way of responding to a serious threat to your circulation and oxygenation.

8. Bluish Discoloration of Lips or Nails (Cyanosis)

Cyanosis refers to a bluish tint to the skin, lips, or nail beds that occurs when blood oxygen levels drop significantly. This symptom indicates that your body tissues are not receiving adequate oxygen—a serious sign that requires immediate medical attention.

In pulmonary embolism, cyanosis occurs because the blood clot prevents oxygen from being absorbed into the bloodstream in the lungs. As a result, oxygen-poor blood circulates through your body, giving your skin and mucous membranes a blue or purple hue.

Where to look for cyanosis:

• Lips and the area around the mouth
• Fingernails and nail beds
• Toenails
• Tongue and inside of the mouth
• Earlobes

Cyanosis is more easily visible in people with lighter skin tones, but it can also occur in those with darker skin. In darker-skinned individuals, check the mucous membranes (inside the lips and mouth), nail beds, and palms of the hands for a grayish or whitish discoloration rather than blue.

The presence of cyanosis indicates severe oxygen deprivation and is a medical emergency. If you or someone you’re with develops a bluish discoloration along with breathing difficulties, call emergency services immediately.

9. Anxiety or Sense of Impending Doom

Many people experiencing a pulmonary embolism report an overwhelming sense of anxiety or a feeling that something is terribly wrong—often described as a “sense of impending doom.” While this may seem like a psychological symptom, it’s actually your body’s physiological response to severe oxygen deprivation and cardiovascular stress.

This intense feeling of dread is not just nervousness or worry—it’s a profound sense that something catastrophic is happening. It occurs because your brain detects that your body is in serious danger, even before you consciously recognize all the physical symptoms.

Psychological symptoms of PE:

• Sudden, intense anxiety or panic
• Feeling of impending death or doom
• Restlessness or inability to get comfortable
• Sense that something is seriously wrong
• Difficulty concentrating or thinking clearly

It’s important not to dismiss these feelings as “just anxiety,” especially if they’re accompanied by physical symptoms like chest pain, shortness of breath, or rapid heartbeat. This combination of symptoms requires immediate medical evaluation, as your body may be alerting you to a life-threatening condition.

What Causes Pulmonary Embolism?

Understanding the causes and risk factors for pulmonary embolism is essential for prevention and early recognition. A pulmonary embolism occurs when a blood clot (or rarely, another substance) travels through the bloodstream and becomes lodged in the pulmonary arteries in the lungs.

Primary cause: The vast majority of pulmonary embolisms are caused by deep vein thrombosis (DVT)—blood clots that form in the deep veins of the legs, pelvis, or arms. These clots can break free and travel through the bloodstream to the lungs.

Major risk factors for blood clots and PE:

• Prolonged immobility: Extended periods of sitting or lying down, such as during long flights, car trips, bed rest, or hospitalization, can slow blood flow in the veins and increase clotting risk
• Surgery: Major surgery, especially orthopedic procedures involving the hips, knees, or legs, significantly increases the risk of blood clots due to tissue damage, immobility, and the body’s clotting response to surgery
• Cancer: Certain cancers and cancer treatments can increase substances in the blood that promote clotting, and cancer can directly affect blood vessels
• Pregnancy and postpartum period: Hormonal changes during pregnancy increase clotting factors, and the pressure of the growing uterus can slow blood flow from the legs
• Hormonal medications: Birth control pills and hormone replacement therapy containing estrogen increase the risk of blood clots
• Previous blood clots: Having had a blood clot or pulmonary embolism in the past significantly increases your risk of another occurrence
• Inherited clotting disorders: Some people have genetic conditions that make their blood more likely to clot, such as Factor V Leiden mutation or prothrombin gene mutation
• Obesity: Excess weight increases pressure in the veins of the pelvis and legs, promoting clot formation
• Smoking: Tobacco use affects blood clotting and circulation, increasing the risk of blood clots
• Heart disease: Heart failure and cardiovascular disease increase the risk of clot formation
• Age: Risk increases with age, particularly after age 60
• Trauma or injury: Fractures, especially of the pelvis or legs, can damage blood vessels and increase clotting risk

Less commonly, pulmonary embolism can be caused by substances other than blood clots, including fat droplets from broken bones, amniotic fluid during childbirth, air bubbles, or tumor fragments.

Prevention Strategies

While not all pulmonary embolisms can be prevented, there are several effective strategies to reduce your risk, especially if you have known risk factors.

Stay active and mobile:

• Avoid sitting or lying down for extended periods
• During long flights or car trips, stand up and walk every 1-2 hours
• Do leg exercises while seated: point and flex your feet, rotate your ankles, and lift your knees
• If you’re hospitalized or on bed rest, work with healthcare providers to get moving as soon as safely possible

Maintain a healthy lifestyle:

• Maintain a healthy weight through balanced diet and regular exercise
• Quit smoking or don’t start—tobacco use significantly increases clotting risk
• Stay well-hydrated, as dehydration can increase blood viscosity
• Exercise regularly to improve circulation and maintain healthy blood vessels

Medical prevention strategies:

• If you’re at high risk for blood clots, your doctor may recommend preventive anticoagulant medications—always follow your healthcare provider’s guidance regarding medications
• Wear compression stockings if recommended by your doctor, especially during long trips or after surgery
• After surgery, follow your healthcare team’s instructions about movement and medications
• Inform your doctor about your personal or family history of blood clots before starting hormonal medications

Be aware of your risk:

• Know your personal risk factors for blood clots
• Discuss your risk with your doctor before surgery, long trips, or starting new medications
• If you have a genetic clotting disorder, make sure all your healthcare providers are aware
• Learn the symptoms of DVT and PE so you can seek help quickly if they occur

Prevention is particularly important for people undergoing surgery, those with limited mobility, pregnant women, cancer patients, and anyone with a history of blood clots. Talk to your healthcare provider about your specific risk factors and appropriate prevention measures.

Frequently Asked Questions

How quickly do pulmonary embolism symptoms appear?

Pulmonary embolism symptoms typically appear suddenly and without warning. The onset is usually rapid—within minutes to hours of the clot lodging in the lung. However, small clots may cause milder symptoms that develop more gradually over days. If you have any symptoms suggestive of PE, seek medical attention immediately regardless of how quickly they appeared.

Can you have a pulmonary embolism without knowing it?

Yes, it’s possible to have a small pulmonary embolism with mild or no noticeable symptoms, sometimes called a “silent” PE. These are often discovered incidentally during imaging tests performed for other reasons. However, even small clots can be serious and may lead to complications, so medical evaluation is important even for subtle symptoms.

Is pulmonary embolism pain constant or does it come and go?

Chest pain from pulmonary embolism is typically constant, though its intensity may vary. The pain characteristically worsens with deep breathing, coughing, or physical activity. Unlike some other types of chest pain that come and go, PE pain usually persists until treatment begins. Any pattern of chest pain combined with shortness of breath warrants immediate medical evaluation.

What is the difference between a blood clot in the lung and pneumonia?

While both conditions can cause chest pain, cough, and shortness of breath, there are important differences. Pneumonia is an infection that typically develops gradually with fever, productive cough with colored sputum, and worsening symptoms over days. Pulmonary embolism usually has sudden onset, sharp pleuritic chest pain, and may include leg symptoms or coughing up blood. However, distinguishing between them requires medical evaluation, as treatment differs significantly.

Can young, healthy people get pulmonary embolism?

Yes, although less common, pulmonary embolism can occur in young, otherwise healthy individuals. Risk factors in younger people include use of hormonal birth control, pregnancy, prolonged immobility (such as during gaming or long flights), smoking, obesity, or undiagnosed clotting disorders. Anyone experiencing symptoms of PE should seek medical attention regardless of age or perceived health status.

How serious is a pulmonary embolism?

Pulmonary embolism is a serious, potentially life-threatening condition that requires immediate medical treatment. The severity depends on the size and number of clots and how much of the lung is affected. Approximately 30% of people with untreated PE die, but with prompt diagnosis and treatment, the mortality rate drops to less than 8%. This is why recognizing symptoms and seeking immediate medical care is crucial.

What should I do if I suspect I have a pulmonary embolism?

If you experience symptoms suggestive of pulmonary embolism—especially sudden shortness of breath, chest pain that worsens with breathing, rapid heart rate, or coughing up blood—seek emergency medical care immediately. Call emergency services or have someone drive you to the nearest emergency room. Do not wait to see if symptoms improve, as pulmonary embolism can be rapidly fatal without treatment. Time is critical in PE management.

Can stress or anxiety cause symptoms similar to pulmonary embolism?

Anxiety and panic attacks can cause some symptoms that overlap with PE, including shortness of breath, rapid heartbeat, chest tightness, and sweating. However, anxiety typically doesn’t cause the sharp, pleuritic chest pain characteristic of PE, coughing up blood, leg swelling, or cyanosis. If you have risk factors for blood clots or if your symptoms feel different from previous anxiety episodes, seek medical evaluation. It’s better to have symptoms checked than to assume they’re “just anxiety” when they could indicate a life-threatening condition.

References:

• Mayo Clinic – Pulmonary Embolism
• National Heart, Lung, and Blood Institute – Pulmonary Embolism
• Centers for Disease Control and Prevention – Venous Thromboembolism
• Johns Hopkins Medicine – Pulmonary Embolism
• American Heart Association – Venous Thromboembolism