Five warning signs of a blood clot that should never be ignored

HealthNeel Achary21 Sept 2026

Center for Vein Restoration physicians urge patients to take sudden, unexplained leg symptoms seriously

GREENBELT, Md. — Leg pain or swelling can be easy to dismiss as muscle strain, but Center for Vein Restoration (CVR) physicians are reminding patients that sudden symptoms without an obvious injury may signal deep vein thrombosis, or DVT.

DVT occurs when a blood clot forms in a deep vein, usually in the leg. A clot can break loose and travel to the lungs, causing a potentially life-threatening pulmonary embolism, or PE.

"Deep vein thrombosis can present with symptoms that are easy to overlook, such as swelling, warmth, or pain in one leg," said Sanjiv Lakhanpal, MD, FACS, President and CEO of Center for Vein Restoration. "Recognizing these signs early and seeking prompt evaluation is critical, since an untreated clot can travel to the lungs and become a serious medical emergency."

Five warning signs of a blood clot

Common signs of DVT include:

  1. Swelling in one leg
  2. Unexplained pain or tenderness
  3. Warmth in the affected area
  4. Redness or skin discoloration
  5. Sudden changes without an obvious explanation

A blood clot in the leg may feel like aching, cramping, soreness or tenderness in the calf or thigh. These symptoms can feel similar to a pulled muscle, which is why unexplained changes should not automatically be dismissed.

Symptoms alone cannot confirm DVT. A health care professional must evaluate the symptoms and determine whether testing is needed. Some people with DVT may have few or no noticeable symptoms.

CVR offers a DVT rule-out service for same-day or next-day diagnosis and treatment plans. Call our hotline number at 877-SCAN-DVT (877-722-6388).

When a blood clot becomes an emergency

If part of a clot travels to the lungs, it can cause a pulmonary embolism. Warning signs of a PE can include sudden difficulty breathing, chest pain, a rapid or irregular heartbeat, coughing up blood, lightheadedness or fainting.

The Centers for Disease Control and Prevention recommends seeking medical attention for possible DVT symptoms and immediate medical attention for possible PE symptoms.

“If one leg suddenly becomes swollen, painful, warm or discolored without a clear reason, it is important to get it checked,” said Dr. Lakhanpal. “Symptoms that could indicate a pulmonary embolism require immediate care.”

About Center for Vein Restoration

Center for Vein Restoration is the nation's largest physician-led vein care organization, with 130+ locations across 23 states. CVR is dedicated to expanding access to world-class vein care through a network of highly credentialed specialists, advanced treatment technology, and a physician-first model of care for treating chronic venous insufficiency, varicose veins, spider veins, and related conditions using minimally invasive, in-office procedures. Visit centerforvein.com.