A nasal drug delivery system and method of delivering a predetermined amount of medication to the nasal epithelia. The system including a container containing a substance to be delivered into the nasal passages of a user. The nasal drug delivery system also includes a nasal shaft extending from the drug delivery system for placement in or around the nose of user, the nasal shaft is in fluid communication with a valve of the container, and an oral shaft, extending from the drug delivery system for placement in the mouth of a user. The nasal drug delivery system also comprises a pressure activated diaphragm trigger, wherein upon application of pressure to the oral shaft triggers the release of a predetermined amount of a substance from the container to the nasal shaft. The method includes steps of inserting the oral shaft into the mouth of a user, inserting the nasal shaft into or around the nose of a user, pressurizing the oral shaft which activates the trigger, and releasing a predetermined amount of medicament from the container into the nasal shaft and into the nasal passage of the user.