FDA issued a draft guidance dated April 27, 2018 titled: “Multiple Function Device Products: Policy and Considerations.” This guidance expands on when and how FDA intends to assess the impact of other functions that are not the subject of a premarket review on the safety and effectiveness of a device function subject to FDA review. It stresses that the potential impact of unregulated functions on safety and effectiveness of regulated functions will still be assessed so the degree of design segregation to minimize potential side affects is considered important.
This is consistent with concepts from AAMI TIR32 and IEC 80002-1 for Medical Device Software Risk Management. It also explicilty states that functionality legally meeting the definition of a medical device, but that is under FDA enforcement discretion, will be treated the same as unreglated functions. If an unregulated function could adversely impact the regulated functions, Section VII identifies additional information to be provided in a premarket submission. This includes Architecture and Design detail adequate to understand potential side effects of the unregulated functions and specific risk analysis. The full draft guidance can be viewed here.