A security device for a patient-controlled analgesia (PCA) device receives a word or series of words spoken into it as a command by a patient and creates a voice print characteristic of the patient. A subsequent receipt of a voiced command is converted into a test voice print and compared to the patient's...http://www.google.com/patents/US6899695?utm_source=gb-gplus-sharePatent US6899695 - Medication security apparatus and method
