What are the symptoms of a blood clot in the leg?
Last updated September 3, 2026.
The DVT signature: swelling in one leg, calf pain or tenderness, warmth, and redness, often starting as a cramp that will not go away. It warrants same-day evaluation, not watchful waiting. The one-sided pattern is the tell; both legs swollen points elsewhere. Pain typically worsens with standing or walking, and roughly half of clots are subtler, so risk factors matter: recent surgery or hospitalization, long immobility, estrogen-containing birth control, pregnancy and postpartum weeks, cancer, obesity, smoking, and any prior DVT. The two hard rules: never massage the leg, and never wait it out, because the feared event is the clot traveling to the lungs. The workup is fast and noninvasive: a D-dimer blood test and compression ultrasound, with blood thinners as the highly effective treatment when confirmed. The escalation that changes everything: leg symptoms plus sudden shortness of breath, sharp chest pain, or coughing blood means pulmonary embolism, and that is a 911 call, not a callback to the clinic.
What to do
- One leg, swollen, warm, tender: same-day care today.
- Cramp that will not quit: treat it as a possible clot, especially with risk factors.
- No massage, no walking it off: keep the leg still.
- Expect ultrasound and a blood test: diagnosis is quick.
- Breathlessness or chest pain: 911 immediately.
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