Abstract: Systems, devices, and techniques are disclosed for differentiating a therapeutic dose and a priming event to properly administer medication to patients. In one example aspect, a method for differentiating therapeutic doses and priming events in administering a medication to a patient includes determining a time window for monitoring dispensing of the medication by an injection pen device. Multiple dispense events each releasing an amount of the medication occur in the time window. The method also includes classifying dispense events prior to a last dispense event in the time window as priming events or therapeutic doses and designating the last dispense event in the time window as a therapeutic dose for facilitating calculation and tracking of a dosage amount for the patient.