An electrotransport device (20) for delivering one or more therapeutic agents through the skin includes electrodes (30,32) for contacting the skin (34), at least one electrode containing the agent, a power source (22) for generating electrical current (I_L) for delivering the agent, a current generating and controlling means (24), and a disabling means (26) for permanently and irreversibly disabling the current. The disabling means (26) may include a timer means (66), a counter means (82), or a body parameter sensor (134) and limit comparator (132) to effect permanent disabling. The disabling means may be a permanent transition to a disabled logic state, a permanent discharge of a power supply source (22), or a permanent diversion of electrotransport current from the electrodes (30,32), or a combination of the above. The permanent disabling means may include a circuit connection means (304,308,326,328) having a frangible conducting member (332) which permanently fractures and causes an irreversible open circuit in the connection to the electrodes (334,342) upon removing a disposable/single use electrode assembly (300) from a reusable portion of an electrotransport device.