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What is Fludarabine and explain in detail?
Fludarabine is a purine analogue and antineoplastic agent.   It is generally used as its 5-O-phosphorylated form known as fludarabine phosphate,
sold under the brand name Fludara among others.  It is a chemotherapy medication used in the treatment of leukemia and lymphoma. These include chronic lymphocytic leukemia, non-Hodgkins lymphoma, acute myeloid leukemia, and acute lymphocytic leukemia. It is given by injection into a vein or by mouth.Common side effects include nausea, diarrhea, fever, rash, shortness of breath, numbness, vision changes, and feeling tired. Severe side effects include brain dysfunction, low blood cell counts, and lung inflammation. Use in pregnancy will likely result in harm to the fetus. Fludarabine is in the purine analog family of medications and works by interfering with the duplication of DNA.Fludarabine was approved for medical use in the United States in 1991. It is on the World Health Organizations List of Essential Medicines.

Medical uses
Fludarabine is highly effective in the treatment of chronic lymphocytic leukemia, producing higher response rates than alkylating agents such as chlorambucil alone.
Fludarabine is used in various combinations with cyclophosphamide, mitoxantrone, dexamethasone and rituximab in the treatment of indolent non-Hodgkins lymphomas.  As part of the FLAG or FLAMSA regimen, fludarabine is used together with cytarabine and granulocyte colony-stimulating factor in the treatment of acute myeloid leukaemia.  Because of its immunosuppressive effects, fludarabine is also used in some conditioning regimens prior to allogeneic stem cell transplant.

Side effects
Fludarabine is associated with profound lymphopenia, and as a consequence, increases the risk of opportunistic infections. People who have been treated with fludarabine will usually be asked to take co-trimoxazole or to use monthly nebulised pentamidine to prevent Pneumocystis jiroveci pneumonia