Brief Answer:
Pedal edema.

Detailed Answer:
Hello,

Thanks for the question.

Foot swelling without injury is suggestive of pedal edema. Retention of water in the soft tissue is the cause of such swelling.This kind of swelling is not specific for one particular cause and can be seen in various conditions. Few such conditions are venous insufficiency in leg, diseases of heart ,kidney .liver,lung etc, lymphedema, hypertension,allergies and even pregnancy .

Usually diagnosis is reached with help of detailed medical history , clinical examination and few investigations.So I would suggest you to see a doctor sooner. The treatment is usually directed towards the underlying cause. Most patients are treated with diuretics.

Please ask if you want me to explain anything.Regards

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