Leg swelling: causes, warning signs & what to do
Swollen legs or ankles are common — often from standing, heat or minor causes. Swelling in one leg, or with breathlessness, can be serious.
Common causes of leg swelling
- Standing/sitting for long periods; heat
- Venous insufficiency (weak leg veins)
- Heart, kidney or liver problems (both legs)
- A blood clot (DVT) — usually one leg
- Injury or infection (one leg, red/hot)
- Certain medicines; pregnancy
When to see a doctor urgently
- One swollen, painful, warm or red calf — seek urgent care (possible clot)
- Leg swelling with chest pain or breathlessness — call emergency services
- Sudden swelling with skin breakdown or severe pain
- Swelling with reduced urine or yellowing of the skin
Frequently asked questions
Is swelling in both legs or one leg more concerning?
One-sided swelling that is painful, warm or red can be a blood clot (DVT) and needs urgent assessment. Both-legs swelling more often points to heart, kidney or vein causes.
How can I reduce mild leg swelling?
Elevate the legs, move regularly, avoid long standing, and use compression stockings if advised. Persistent or one-sided swelling should be checked.
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MedDroid is an AI medical assistant and can make mistakes. It provides general health information, not a diagnosis or medical advice — always consult a qualified clinician. In an emergency, contact your local emergency number immediately.