Improved systems and methods for medicine delivery, and in particular, improved insulin pen needles and related devices are provided. Smart injection devices record and transfer data including medicine level, delivered dose, dose confirmation, and dose time and date. Additional data captured may include glucose concentration, insulin level, carbohydrates ingested, stress level, exercise, blood pressure, and glucose high and low excursion events. Various means of data collection and analysis are provided and systems can identify and flag patients who require intervention. Smart sleeves and add sensing capability to standard insulin pens. Pen needles are provided with sensing capability to confirm and measure doses delivered by insulin pen. A two-part pen cap include a primary sleeve that connects to the insulin pen and an end cap that provides for capturing the time of dose delivery, and monitoring the hold time for a dose delivery after plunger movement.
