Brief Answer:
Common causes: heart/liver/kidney diseases and medication side effects

Detailed Answer:
Hello and welcome,

Variety of disorders may cause leg swelling. The underlying mechanism of leg swelling is fluid retention.
Is the swelling on one leg (unilateral) or both (bilateral)?

Unilateral leg swelling is most common from local problems such as vein problems (obstruction of venous or lymph vessels), osteoarthritis, traumas, or cellulitis. Bilateral leg swelling is commonly from systemic disorders such as heart disease (right ventricular failure, chronic heart failure), liver diseases, kidney diseases, malnutrition and from medication side effects.
The underlying cause of the leg swelling might be obvious from patient presentation and history, or it may take thorough medical investigation to find it out. Usually doctors order complete blood count, liver function tests, renal function panel. If the heart problem is suspected EKG and echocardiogram is ordered.
Among your medications pantoprasole, baclofen and oxybutinin may rarely cause leg swelling as well.

Hope, this information is helpful for you. Please, feel free to ask me if there is anything else you need to know.

Wish you good health.

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