Brief Answer:
vein insufficiency, heart failure, etc

Detailed Answer:
Hello,

you haven't given any information about your medical history, so I'll just make up a list for you with some of the most common causes of bilateral leg swelling.

- vein insufficiency: faulty vein valves cannot handle the pressure of gravity and blood stays in the legs for too long, causing swelling. An ultrasound scan of the veins would suffice to confirm or exclude it.
- heart failure: leg swelling is a common complaint in patients with heart failure. An ultrasound scan of the heart (echo) is the right test for the assessment of your heart's condition.
- drugs: certain drugs may cause leg swelling. A very common one is amlodipine (and other calcium channel blockers).
- thyroid disease: it usually causes more persistent leg swelling but it's another cause in the list... Measuring serum TSH is enough as an initial approach.
- low blood proteins, particularly in patients with renal (proteinuria) or liver (cirrhosis) problems. Serum total proteins and albumin measurement is enough to find out.

Leg elevation is helpful most of the times. Depending on the cause, more specific treatments may apply, like diuretics for heart failure.

I hope it helps!
Please contact me again, if you'd like to discuss it further.

Kind Regards!

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