Blood Clot Leg Symptoms: 5 Signs You Shouldn’t Ignore

Spotting the Early Signs of a Blood Clot

When Leg Pain Could Be a Medical Emergency

A sore leg doesn’t always mean a pulled muscle. If the pain comes on suddenly, feels different than usual, or comes with other symptoms, it could be a blood clot. Knowing the early blood clot leg symptoms can make the difference between quick treatment and serious complications.

Here are five signs to watch for.

1. Swelling in One Leg

Sudden swelling in one leg — especially below the knee — is a common early symptom of deep vein thrombosis (DVT). The swelling may feel tight or look noticeably larger than your other leg.

2. Unexplained Pain or Cramping

Pain from a DVT often feels like a cramp or pulled muscle but doesn’t go away with rest or stretching. It usually affects the calf or back of the thigh.

3. Warmth or Redness Over the Vein

The skin over the clot may feel warm to the touch or appear red or discolored. These are signs of inflammation caused by the blockage.

4. Tenderness to the Touch

If your leg feels sore when touched — especially in the calf — and you didn’t recently injure it, this could be related to a clot forming deep in the vein.

5. Leg Heaviness or Fatigue

Many patients describe a dull ache, pressure, or tiredness in the affected leg, even when sitting or lying down. It may feel like gravity is pulling harder on one side.

What to Do If You Notice These Symptoms

Don’t wait. Blood clots can grow quickly and lead to serious complications like pulmonary embolism if they travel to the lungs. If you experience any of these blood clot leg symptoms, especially more than one, get medical care right away.

How Imaging Confirms the Diagnosis

The fastest way to confirm a suspected DVT is with a venous ultrasound — a quick, noninvasive scan that looks at blood flow in your legs.
If a clot is found, interventional radiologists can perform clot-directed therapy (CDT) to break it up and restore normal circulation.

NIH: See how ultrasound helps detect DVT early

Don’t Ignore the Signs

Even if your leg pain seems mild, these early warning signs should never be ignored. Imaging and treatment are fast — and early action can prevent life-threatening complications.

Check out more patient-first vascular care insights on our blog.