You can elevate your legs to reduce swelling in your knees. When there is knee swelling, you can elevate your legs above the level of the heart, so that under the effect of gravity, it can promote the return of venous blood flow, which is conducive to the absorption of swelling subside. However, there are many causes of knee swelling, such as trauma, osteoarthritis, infection, etc. Therefore, at the same time of leg elevation, it is also necessary to treat the primary disease that causes knee swelling in order to have a better effect. If the knee swelling is caused by trauma, cold compresses can be applied during the acute injury period and hot compresses can be applied during the recovery period. You can also apply drugs, such as diclofenac sodium, heptaphyllum saponin sodium and other treatments; you can also carry out rehabilitation exercises, such as muscle contraction exercises, ankle pump exercises, etc., which are also conducive to swelling. Knee swelling, should go to the hospital in time to further identify the cause of the disease, and then targeted treatment. The above drugs need to be applied under the guidance of a physician.