Understanding Deep Vein Thrombosis (DVT)

Deep Vein Thrombosis (DVT) occurs when a blood clot forms in a deep vein, most often in the legs. These clots can partially or completely block blood flow in the vein and may cause symptoms such as leg swelling, pain, warmth, or tenderness.

While some cases may develop gradually, others can appear suddenly. Deep vein thrombosis is an important medical condition because a clot can sometimes move through the bloodstream and affect other parts of the body.

Understanding the symptoms and causes of DVT can help people recognize when medical evaluation may be necessary.

diagram showing deep vein thrombosis blood clot forming in a leg vein

Find a Specialist

Explore Related Symptoms

What Is Deep Vein Thrombosis?

Deep vein thrombosis occurs when a blood clot forms in one of the deep veins of the body, most commonly in the legs. Veins normally carry blood back toward the heart, but a clot can obstruct this flow and cause pressure within the vein.

The condition may develop when blood flow slows down, when the blood becomes more prone to clotting, or when the lining of a vein becomes damaged.

Deep vein thrombosis can sometimes occur without noticeable symptoms, but in other cases it may cause swelling, pain, or tenderness in the affected leg.

Symptoms of Deep Vein Thrombosis

Symptoms may vary depending on the location and size of the clot.

Swelling in one leg
Pain or tenderness in the leg
Warmth in the affected area
Red or discolored skin
Leg heaviness or tightness
Pain that worsens when standing or walking
Visible surface veins becoming more noticeable
Cramping or soreness in the calf

diagram showing symptoms of deep vein thrombosis including leg swelling pain and redness

medical diagram showing deep vein thrombosis blood clot in the leg

Why Deep Vein Thrombosis Happens

Deep vein thrombosis may develop when blood flow in the veins slows or when the body becomes more prone to forming clots. This can occur during long periods of inactivity, after surgery, or when certain medical conditions affect blood clotting.

Damage to the lining of the vein can also increase the risk of clot formation. When these factors combine, blood may clot inside the vein instead of flowing normally through the circulation.

Risk Factors for Deep Vein Thrombosis

Several factors may increase the likelihood of developing a blood clot in the veins.

Long periods of sitting or inactivity
Recent surgery or injury
Pregnancy
Certain medications that affect clotting
Family history of blood clots
Obesity
Smoking
Aging

When Should You See a Specialist?

Symptoms such as sudden swelling, pain, or warmth in one leg may indicate a blood clot and should be evaluated promptly. A specialist can assess circulation and determine whether further testing is needed.

Because deep vein thrombosis can sometimes lead to serious complications, early evaluation is important when symptoms appear suddenly or worsen quickly.

Consider seeking evaluation if you experience:

swelling in one leg
pain or tenderness in the calf
warmth in the affected leg
redness or discoloration of the skin
sudden leg discomfort after long travel
symptoms that appear suddenly or worsen quickly

vascular specialist evaluating patient during medical consultation

How Deep Vein Thrombosis May Be Evaluated

A specialist may begin by reviewing symptoms and examining the affected leg. Imaging tests are often used to confirm the presence of a blood clot and evaluate blood flow in the veins.

One of the most common tests used is duplex ultrasound, which allows doctors to visualize the veins and detect blockages or clots. Additional tests may sometimes be used depending on the situation.

These evaluations help determine whether treatment is needed and how to prevent complications.

doctor performing vascular ultrasound to evaluate the leg

What Are You Experiencing?

These symptoms may sometimes appear alongside deep vein thrombosis.

Concerned About Deep Vein Thrombosis?

Learn more about conditions that affect circulation in the legs and connect with specialists who evaluate and treat vascular health problems.

Find a Specialist

Explore Symptoms

Understanding Deep Vein Thrombosis (DVT)

What Is Deep Vein Thrombosis?

Symptoms of Deep Vein Thrombosis

Why Deep Vein Thrombosis Happens

Risk Factors for Deep Vein Thrombosis

When Should You See a Specialist?

How Deep Vein Thrombosis May Be Evaluated

What Are You Experiencing?

Leg Pain

Leg Cramps

Leg Swelling

Restless Legs

Leg Numbness / Tingling

Burning Sensation in Legs

Cold Feet

Heavy Legs

Concerned About Deep Vein Thrombosis?

Understanding Deep Vein Thrombosis (DVT)

What Is Deep Vein Thrombosis?

Symptoms of Deep Vein Thrombosis

Why Deep Vein Thrombosis Happens

Risk Factors for Deep Vein Thrombosis

When Should You See a Specialist?

How Deep Vein Thrombosis May Be Evaluated

What Are You Experiencing?

Concerned About Deep Vein Thrombosis?

Help My Legs

Contact Us

Hours of Operation