Contemporary health care systems are increasingly incorporating medical sensors and automatically controlled actuation devices to deliver smart and proactive health services. The embedded devices used in this regard continuously interact with the human body or patient either through sensing of physiological signals or through the execution of critical medical actuation such as drug delivery. Given the high risks in their deployment, patient safety during operation of these Cyber-Physical Medical Systems (CPMSes) has to be guaranteed even before use. This paper proposes CPS-MAS, a cyber-physical medical system modeling and analysis framework for safety verification. However, given the complex nature of interaction of the medical devices with the human body, characterized by non-linearity, transport delay, spatio-temporal effects, and nontrivial aggregation of interaction during networked operation of devices, such modeling and analysis is a challenging problem. The paper describes an approach to formal modeling and analysis of CPMSes with the help of two examples related to analgesic drug delivery and chemotherapy.