Rituximab is used to treat certain types of cancer (e.g., non-lymphoma, Hodgkin's chronic lymphocytic leukemia) either alone or in combination with other medications. A monoclonal antibody is a type of medicine. It works by binding to specific proteins on the surface of some cells and triggering an immune response. This may help kill such cells that have grown into tumors. Rituximab is made from rabbits injected with human blood cells. The resulting serum is then mixed with alcohol to remove any contaminants before being frozen in aliquots for future use. The medication is administered as a shot into a large muscle, such as the thigh. It must be taken very carefully not to spill any of the liquid substance. Doing so could cause serious harm due to the risk of infection. It takes about two weeks for all of the antibodies in rituximab to work their way through your body. During this time, you should avoid exposure to sunlight because the ultraviolet rays can damage the photosensitive chemicals contained within the package insert. Also, women who are pregnant or may become pregnant should not take rituximab.