Purinethol

Mercaptopurine works by stopping the abnormal blood cells from multiplying. It does this by being incorporated into the cells’ genetic material, DNA and RNA. Both DNA and RNA are needed for cells to grow, repair themselves and multiply. Mercaptopurine causes problems with the production of DNA and RNA in the cancer cells, and this causes the cells to grow in an unbalanced way, resulting in the death of the cells.