Devices, systems, and methods are provided for adherence monitoring and patient interaction. In general, the devices, systems, and methods can facilitate a patient's adherence to a medication schedule and can facilitate monitoring and tracking of the patient's adherence to the medication schedule. In one embodiment, a medical accessory such as a cap is provided that can be configured to attach to existing medication dispensers, such as asthma inhalers, or to be integrated into a custom-made medication dispenser. The accessory can be configured to provide a notification to the patient when medication is due. The accessory can be configured to detect usage of the dispenser. The accessory can be configured to provide data regarding dispensing of the medication to an external device. The data can be analyzed and provided for visualization on a user interface.