A device for monitoring adherence of a patient to a prescribed regimen, the device comprising: a pulmonary delivery device comprising a pressurized cartridge for accommodating a drug according to the prescribed regimen and a nozzle through which the drug is released; an adapter comprising an inlet, an outlet and a chamber between the inlet and outlet, wherein the inlet is in fluid communication with the nozzle for admitting the drug into the chamber, wherein the chamber is defined by a hollow wall; a dispenser coupled with the adapter for allow the drug to enter the dispenser from the chamber; and at least one sensor for detecting a parameter change associated with a movement of the drug from the pulmonary delivery device to the dispenser and generating a feedback signal based on the parameter change, wherein the feedback signal is processed for generating an indicator signal representative of delivery of the drug to the patient, wherein the sensor comprises: a substrate; a hermetical enclosure formed on a top surface of the substrate, wherein the substrate and the hermetical enclosure together define a hermetical cavity; a microcontroller and a wireless link formed on the top surface of the substrate and within the hermetical cavity; a plurality of sensor units formed on a bottom surface of the substrate and outside of the hermetical cavity; a battery unit formed within the hermetical cavity for powering the microcontroller, the wireless link and the plurality of sensors; and a protective coating for sealing the substrate, the hermetical enclosure, the microcontroller, the wireless link, the plurality of sensor units and the battery unit. a pulmonary delivery device comprising a pressurized cartridge for accommodating a drug according to the prescribed regimen and a nozzle through which the drug is released; an adapter comprising an inlet, an outlet and a chamber between the inlet and outlet, wherein the inlet is in fluid communication with the nozzle for admitting the drug into the chamber, wherein the chamber is defined by a hollow wall; a dispenser coupled with the adapter for allow the drug to enter the dispenser from the chamber; and at least one sensor for detecting a parameter change associated with a movement of the drug from the pulmonary delivery device to the dispenser and generating a feedback signal based on the parameter change, wherein the feedback signal is processed for generating an indicator signal representative of delivery of the drug to the patient, wherein the sensor comprises: a substrate; a hermetical enclosure formed on a top surface of the substrate, wherein the substrate and the hermetical enclosure together define a hermetical cavity; a microcontroller and a wireless link formed on the top surface of the substrate and within the hermetical cavity; a plurality of sensor units formed on a bottom surface of the substrate and outside of the hermetical cavity; a battery unit formed within the hermetical cavity for powering the microcontroller, the wireless link and the plurality of sensors; and a protective coating for sealing the substrate, the hermetical enclosure, the microcontroller, the wireless link, the plurality of sensor units and the battery unit. a substrate; a hermetical enclosure formed on a top surface of the substrate, wherein the substrate and the hermetical enclosure together define a hermetical cavity; a microcontroller and a wireless link formed on the top surface of the substrate and within the hermetical cavity; a plurality of sensor units formed on a bottom surface of the substrate and outside of the hermetical cavity; a battery unit formed within the hermetical cavity for powering the microcontroller, the wireless link and the plurality of sensors; and a protective coating for sealing the substrate, the hermetical enclosure, the microcontroller, the wireless link, the plurality of sensor units and the battery unit.