The new concepts of ubiquitous computing are being integrated in healthcare technologies and led to the emergence of pervasive healthcare systems. This development is shifting the care that patients get to the comfort of their own homes. This paper surveys existing pervasive healthcare solutions including those developed in academia as well as commercial solutions from the industry sector. This paper also develops a set of criteria, which were used to classify and compare these solutions. These criteria are: integrity, confidentiality, mobility and context-awareness. We discuss some drawbacks of existing solutions, and propose future directions in pervasive healthcare. Finally, the paper draws some guidelines and best practices, which are predicted to shape future pervasive healthcare systems.