Radio Frequency Identification (RFID) systems are widely used in access control, transportation, real-time inventory and asset management, automated payment systems, etc. Nevertheless, the use of this technology is almost unexplored in healthcare environments, where potential applications include patient monitoring, asset traceability and drug administration systems, to mention just a few. RFID technology can offer more intelligent systems and applications, but privacy and security issues have to be addressed before its adoption. This is even more dramatical in healthcare applications where very sensitive information is at stake and patient safety is paramount. In Wu et al. (J. Med. Syst. 37:19, 43) recently proposed a new RFID authentication protocol for healthcare environments. In this paper we show that this protocol puts location privacy of tag holders at risk, which is a matter of gravest concern and ruins the security of this proposal. To facilitate theimplementation of secure RFID-based solutions in the medical sector, we suggest two new applications (authentication and secure messaging) and propose solutions that, in contrast to previous proposals in this field, are fully based on ISO Standards and NIST Security Recommendations.