ADHESION DETECTION FOR A MEDICAL PATCH

A patch includes: an adhesive layer configured to adhere to skin of a person, and a communication circuit that includes a current sensor and a resonant circuit. The resonant circuit includes a coil antenna and a capacitor. The current sensor is configured to sense current in the communication circuit over time, where the sensed current has a known relationship to current through the coil antenna. The patch further includes at least one of a circuit or a processor configured to at least perform: determining that a change in the current through the coil antenna is greater than a threshold change, and providing, based on the determination, an indication that the adhesive layer is at least partially detached from the skin of the person.