A monitoring system (2) for monitoring a dispensing device (4, 4, 4", 4", 4") is disclosed. The monitoring system (2) comprises a communication unit (50, 50, 50", 50", 50"). The communication unit (50, 50, 50", 50", 50") comprises communication means (6) configured to communicate wirelessly with a data management device (8) or a central data management unit (58). The communication unit (50, 50, 50", 50", 50") comprises means for acknowledging and registering when a prescribed dose of a medicine or a dietary supplement has been taken. The monitoring system (2) is a separate unit (50) configured to be used with a separate dispensing device (4, 4, 4", 4", 4"). The separate unit (50) comprises the communication unit (50, 50, 50", 50", 50") and means for being detachably attached to the dispensing device (4, 4, 4", 4", 4").
