HAMA stands for Human Anti-Mouse Antibodies. It is an antibody found in humans that reacts to immunoglobins found in mice. HAMA can be produced in some individuals who have been treated with mouse monoclonal antibodies, which can elicit an immune response resulting in the presence of HAMA in human individuals. The presence of HAMA in patient samples can lead to false positive and false negative results in immunoassays. HAMA can interfere with immunoassay measurements, and HAMA interferences can give false positive or negative immunoassay results. HAMA can also decrease the effectiveness of treatments or create a future reaction if the patient is given a subsequent treatment containing mouse antibodies. The existence of HAMA can complicate laboratory measurements.