ABSTRACT: A buzzword big data is used to recognize the datasets due to their large size and complexity. It is rapidly expanding in all areas such as science and engineering physical, biological and biomedical sciences. It is the collection of a large volume of structured and unstructured data. The big data is evolution is from business applications, agriculture, healthcare, social media and sensor data and so on. The data in healthcare is increasing quickly and is expected to increase very much in the coming years. Adoption of an evidence-based approach of big data solutions will play a critical role in the outcomes of the healthcare industry and providing patient centric treatment. Big data analytics is expanding area with the potential to provide useful insight into healthcare. With the big data and analytics tools and technologies, the predictive system will be designed to identify the increased risk. This paper describes big data analytics, characteristics, and potential and implementation of big data analytics in healthcare. It ends up with a survey of challenges and future directions in the healthcare sector.