Treatment for fluid on the knee depends on the cause and severity of the condition, says Mayo Clinic. If the cause is a minor injury, it may heal on its own or respond well to over-the-counter medications such as ibuprofen. Underlying conditions may be present and need medical care.
There are many potential causes for fluid on the knee, including infection, arthritis, overuse, bursitis and tumors, explains Mayo Clinic. In addition to the swelling, fluid on the knee often causes pain and stiffness in the joint. If over-the-counter medications do not relieve symptoms, oral or injected steroids may be prescribed. Elevating, resting and icing the joint can also help relieve symptoms. Mayo Clinic recommends seeing a doctor if the knee becomes red and warm to the touch.