Nasal medication or drug delivery devices and methods for delivering adjustable or variable metered volumetric doses of medication or drugs to a nasal passageway of a user or patient. Relative movement between portions of a reservoir establish a set volume of medication for delivery. The delivery device may include a nosepiece for fitting into the nostril of the user or patient, a medication or drug reservoir or dosing chamber, and an external reservoir adapter for providing the medication from an external reservoir.