How can I check myself for blood clots?

September 25, 2025 •

5 min read

According to the CDC, as many as 900,000 Americans could be affected by blood clots, including deep vein thrombosis (DVT), every year. Given the serious nature of this condition, it is critical to understand how you can check yourself for blood clots, recognize the signs, and know when to seek professional medical attention.

Quick Summary

You cannot reliably diagnose a blood clot at home, as professional evaluation is required for a definitive diagnosis. Instead of a self-test, it's vital to recognize the potential symptoms, understand risk factors, and seek immediate medical help if you experience concerning signs like unexplained swelling, pain, or shortness of breath.

Key Points

Know the symptoms, don't self-diagnose: It is impossible to reliably check yourself for a blood clot at home, but knowing the warning signs is crucial for knowing when to seek professional help.
DVT symptoms: Look for unilateral swelling, pain, warmth, and skin discoloration in a leg or arm.
Emergency for PE: Seek immediate emergency care if you experience symptoms of a pulmonary embolism, such as sudden shortness of breath or chest pain.
Beware outdated tests: Methods like the Homan's test are unreliable and massaging a potential clot is extremely dangerous.
Professional diagnosis is key: Doctors use a combination of physical exams, blood tests (like D-dimer), and imaging (ultrasound) to make an accurate diagnosis.
Recognize your risks: Be aware of risk factors such as immobility, recent surgery, and pregnancy to stay vigilant.

Recognizing the Warning Signs: What to Look For

While a definitive diagnosis requires a medical professional, knowing the key warning signs is your most important tool. A blood clot's symptoms can vary depending on its location in the body.

Symptoms of a DVT (Deep Vein Thrombosis) in the Leg or Arm

Blood clots most commonly form in the deep veins of the leg, but can also occur in the arms. Symptoms in the limbs often include:

Swelling: An unexplained swelling in one leg or arm. One limb may appear noticeably larger than the other.
Pain: Throbbing, persistent pain or cramping, often starting in the calf or thigh. The pain may worsen when you walk or stand.
Tenderness: The area of the clot may feel tender to the touch.
Warmth: The affected limb might feel warm to the touch compared to the other.
Skin Discoloration: The skin over the area can become red or darkened, though this may be harder to see on darker skin tones.

Symptoms of a Pulmonary Embolism (Clot in the Lung)

A pulmonary embolism (PE) is a life-threatening complication that occurs when a DVT breaks free and travels to the lungs. It requires immediate medical attention. Signs of a PE include:

Sudden, unexplained shortness of breath
Sharp chest pain that gets worse with a deep breath or cough
Rapid or irregular heartbeat
Feeling dizzy, lightheaded, or fainting
Coughing, which may produce bloody sputum

The Dangers of Self-Testing

It is a common misconception that certain at-home maneuvers, such as the Homan's test (flexing the foot to check for pain in the calf), can reliably detect a DVT. This is not true. The Homan's test is outdated and proven to be unreliable. Furthermore, attempting to massage or apply pressure to a suspected clot is extremely dangerous and can cause it to dislodge and travel to the lungs, leading to a PE. Therefore, the best way to "check" yourself is by recognizing symptoms and immediately contacting a healthcare provider.

When to Seek Emergency Medical Care

It is crucial to know the difference between observing symptoms and needing emergency care. You should call 911 or go to the nearest emergency room immediately if you experience any of the symptoms of a pulmonary embolism, such as sudden shortness of breath or chest pain. For less immediate, but still concerning symptoms of a potential DVT, you should contact your doctor as soon as possible. Never wait and see if the symptoms improve on their own.

Medical Diagnosis vs. Self-Assessment


Assessment Method	Accuracy	What It Shows	Safety	Notes
Self-Assessment	Low	Based on subjective symptoms like pain, swelling, and warmth. Can be wrong or misleading.	Medium-High (if done correctly)	Should only be used to decide if professional help is needed; not for diagnosis.
Physical Exam	Medium	A doctor checks for objective signs like tenderness, warmth, and swelling.	High	A doctor uses their expertise to interpret symptoms.
D-dimer Blood Test	High (for ruling out DVT)	Measures a protein fragment (D-dimer) released when a blood clot dissolves.	High	A normal result can often rule out a DVT, but an elevated result requires further investigation.
Duplex Ultrasound	Very High	Uses sound waves to create an image of blood flow in the veins.	High	The standard, non-invasive method for confirming a DVT diagnosis.

Key Risk Factors for Blood Clot Development

Certain factors can increase your risk of developing a blood clot. Knowing these can help you be more vigilant about monitoring your health.

Immobility: Long periods of sitting, such as during air travel, car rides, or hospital stays, can significantly increase your risk.
Surgery and Injury: Major surgery or a severe injury, especially to the legs or pelvis, can increase the chance of a clot forming.
Age: The risk of blood clots increases as you get older, particularly after age 60.
Pregnancy and Childbirth: Hormonal changes and increased pressure on pelvic veins can raise the risk during pregnancy and up to six weeks postpartum.
Smoking: Smoking damages the lining of blood vessels, making clot formation more likely.
Obesity: Carrying excess weight increases pressure on the veins, particularly in the legs.
Certain Medical Conditions: Conditions such as cancer, heart failure, and inflammatory bowel disease are associated with a higher risk.
Hormone Therapy: Birth control pills or hormone replacement therapy can increase risk in some individuals.

What Medical Professionals Do to Check for a Clot

When you see a doctor with suspected symptoms, they will follow a structured process to determine if you have a blood clot. This often includes:

A thorough physical examination.
Taking a detailed medical history, including risk factors.
Ordering a D-dimer test, a blood test that can help rule out a DVT in low-risk individuals.
The most common diagnostic tool is a Duplex Ultrasound, a painless imaging test that can visualize blood flow and detect clots.
In some cases, especially for clots in the lungs or pelvis, other imaging such as a CT or MRI scan may be used.

Prevention is Your Best Defense

While you cannot perform a diagnostic self-check, you can take proactive steps to reduce your risk. These include:

Staying active and moving regularly, especially during long periods of sitting.
Staying hydrated.
Wearing compression stockings, if recommended by your doctor, during long flights or extended immobility.
Avoiding smoking.
Maintaining a healthy weight.
Following your doctor's advice on medications and treatments for any underlying conditions.

Your awareness of symptoms and risk factors is the most effective tool you have. If something feels wrong, don't wait. A prompt call to your doctor is always the safest and best course of action. For more information on understanding and preventing blood clots, consider visiting the National Blood Clot Alliance website.

Conclusion: Prioritize Medical Evaluation Over Self-Diagnosis

In summary, while you can't accurately check yourself for a blood clot at home, you can be vigilant about recognizing the signs and symptoms. A self-assessment should never replace a professional medical evaluation, especially considering the potentially life-threatening nature of a pulmonary embolism. Stay informed about the risk factors, pay close attention to your body, and don't hesitate to seek prompt medical attention if you notice any persistent or concerning symptoms. Your health depends on it.

Frequently Asked Questions

The Homan's sign is an outdated test that involves checking for pain in the calf when the foot is flexed. It is not considered a reliable method for diagnosing a blood clot and should not be used as a substitute for professional medical advice.

Yes, many people with deep vein thrombosis (DVT) experience no symptoms. This makes it even more important to be aware of your risk factors and to seek medical attention if you experience any signs, even if they seem minor.

If you suspect you have a blood clot, especially if you experience chest pain or shortness of breath, you should seek emergency medical care immediately. For less severe but persistent symptoms, contact your doctor as soon as possible for a professional evaluation.

Yes, regular physical activity and movement are crucial for preventing blood clots. For long periods of inactivity, like on a flight, getting up and walking around or doing foot and leg exercises can help prevent clots from forming.

A DVT is a blood clot that forms in a deep vein, most often in the leg. A pulmonary embolism (PE) is a life-threatening condition that occurs when a piece of the DVT breaks off and travels to the lungs, blocking a blood vessel.

Doctors typically use a combination of a D-dimer blood test and a duplex ultrasound. The ultrasound is a non-invasive imaging test that provides a clear picture of the veins to confirm or rule out the presence of a clot.

No, it is extremely dangerous to massage a leg with a suspected blood clot. Doing so could cause the clot to break free, travel to the lungs, and lead to a potentially fatal pulmonary embolism.