Abstract: A health care monitoring system and network for monitoring a patient's use of medications, physiological conditions, and/or the environment around the patient. The system takes advantage of a hierarchical nodal network to allow for the transfer of information from sensors to authorized users of the network while providing personal control of sensitive information and providing a distributed database structure for increased data security. In one embodiment, sensors transmit information to wearable personal data recorders that use a combination of random access and overwriting to store information in a time-sequenced organization.