The increasing accumulation and availability of health data, added to the recent progress in artificial intelligence, gave way to a more advanced health analytic tool and predictive models. The study derived its importance from AI tools and technologies' increasingly active role in modern healthcare innovation. The paper reviews the literature on AI applications in healthcare regarding identifying trends, challenges, and future developments of AI applications in health. This review throws light on some major aspects of healthcare, such as diagnosis, recommendation for treatment, design and delivery of a treatment plan, prediction of epidemic conditions regarding patients' care, and hospital management. Information was collated from various points in time. The paper reviews the current state-of-the-art research in AI and health, pinpoints trends and needs for better AI tools in health, indicates the way to advance this interplay, and discusses remaining AI challenges that must be overcome so that full benefits from health AI can be reaped.