Present review article elucidate radiation generated effects on blood brain barrier, tissues, cells and organ systems of human body. Radiation is used to finish brain metastasis and tumor ablation but repetitive exposure of radiation induces multiple deformities almost in all tissues or organs. Low physiological dosage of radiation is provided to increase BBB permeability by loosing its structural integreity of BBB to administer the therapeutic drugs. But repeatitive use of radiation for diagnosis and therapeutic purposes generates severe side effects both instant and delayed. Irradiation causes instant effects on central nervous system (CNS) while late effects including demyelination, gliosis and necrosis, inflammation of photoreceptors, skin, lungs, hematopoietic cells and syndromes of bone-marrow depression and gastrointestinal damage. Radiation generates genotoxic effects in chromosomes, entangle its separation during cell division and disturb replication and transcription of DNA. Radiation exposure imposes intermediate effects like abnormal bonding between adjacent molecules while in germ cells radiation induces transient azospermia and failure of gonadal functions. Radiations also cause aberration of the blood vessels of the brain due to binding of radiation to radioreceptors and induce various syndromes and neurological diseases. In this review article an over view of all possible consequences of radiation exposure on human life and emphasize role of radio - protective medicines and other safety measures is presented. It also suggests use of combination therapies for cancer treatment rather than using radiation alone. No doubt combination therapies will prove better to ablate tumor at an earlier stage and may become landmark discovery in the field of cancer biology.

chemotherapy, radiation, radiation therapy, blood brain barrier, vascular permeability, acute biological effects, disorders and syndromes