Fluid on the knee is another way of saying your knee is swollen. The inflammation from some injury has caused protective fluid to rush to the joint, and the result is swelling. While severe swelling needs to be handled by a medical professional, mild swelling can often be dealt with at home using household first aid items. Knowing how to treat your swollen knee at home can be a real cost saver.
The best possible treatment for swelling is ice therapy. Elevate the knee to hip level or higher, and apply an ice pack to it. Make sure you have a cloth or towel between the ice pack and your skin to prevent frostbite. Apply the cold to the knee for 20 minutes at a time, then allow the skin to warm up for about five minutes, then reapply. Do this for an hour and see if the swelling has gone down.
Stay off the knee. This may seem too simple, but it is often the most effective method to heal it. Curtail your normal activities for a few days, and apply ice and compression, and see if the swelling dissipates. When you are sitting, keep the knee elevated to improve circulation. When lying down, keep the leg elevated with pillows to encourage the excess fluid to drain away from the knee joint.
Use a compression bandage, such as an Ace bandage, to help support the knee while it is healing and to compress the fluid around the knee, encouraging it to move out of the joint and be absorbed into the rest of the body. Make sure the bandage is tight enough to provide support, but not so tight as to cut off circulation. These three simple steps will clear up most cases of fluid on the knee.