The advent of Internet of Things (IoT) has created immense possibilities which are fundamentally altering the way healthcare services are provided around the world. In addition to improving accessibility of healthcare services and patient safety, this has also reduced healthcare expenditures and increased operational efficiency in the healthcare sector. In this regard, Cloud resources are widely used to support near real-time IoT based healthcare applications by performing efficient algorithms on the huge amount of data produced by medical sensor devices. However, response time along with data privacy and security still represent major concerns that inhibit Internet of Things (IoT) medical devices and frameworks from being entrusted as an efficient solution to attain the goal. Of late, there is a burgeoning interestedness towards development of fog and edge based frameworks as a way to counteract the shortcomings of the cloud. The paper offers a review of healthcare related developments from a variety of perspectives, including outbreak control, chronic disease management, neonatal and pediatric treatment, elderly care, and disability management. The paper further examines the challenges hindering the adoption of IoT based healthcare devices and outlines the future research directions.