Swelling of the right foot but not the left foot may be caused by venous thrombosis, which can be treated by medication and surgery. 1. Medication: When venous thrombosis is in chronic stage, it can be treated by medication, which can be taken Rivaroxaban and Dabigatran etexilate capsules under doctor’s instruction. 2. Surgery: When venous thrombosis is in acute stage, it can be treated by surgery, usually open surgery, such as thrombectomy and interventional thrombectomy. After surgery, patients should pay attention to bed rest and forbid rubbing and squeezing the wound to prevent the thrombus from dislodging. When patients appear right foot swelling left foot does not swell, it is recommended to go to the hospital in a timely manner, and under the guidance of the doctor to take medication, remember not to take it privately, so as to avoid adverse effects.