The present invention is generally directed to drug delivery devices that select and dispense multiple doses of a drug. The drug delivery device comprises a drug reservoir attached to the housing (10； 10 ′； 10 ′) and axially relative to the housing (10； 10 ′； 10 ′) for dispensing a dose of drug from the drug reservoir A drive mechanism (30, 40) including a movable plunger (30； 30 ') and releasably connected to the drive mechanism and second relative to the housing (10； 10'； 10 ') for selecting a dose A dose selection element (60, 80； 60 ') that is rotatable in one direction and a housing (10； 10' for initiating dosing of a dose selected by the dose selection element (60, 80； 60 ') A trigger (70； 70 ') that is axially movable relative to 10'), and a limiter (70； 70 ') that selectively enables and prevents axial movement of the trigger (70； 70') depending on the selected dose. 100； 100 ′； 100 ′). The limiter (100； 100 ′； 100 ″； 100 ′) is non-rotatably restrained with respect to the dose selection element (60, 80； 60 ′) and triggers ( 70； 70 ') are axially constrained. One of the limiter (100； 100 ′； 100 ″； 100 ′) and the component member (110； 10 ′) axially connected to the housing (10； 10 ′； 10 ′) is the limiter (100； 100 '； 100 "； 100') and engages the other blocking feature (112； 112 '； 112') of the component members axially connected to the housing (10； 10 '； 10') Including tracks. The track has at least one narrow section that limits relative axial movement between the track and the blocking function (112； 112 ′； 112 ′), and the track and blocking function (112； 112 ′； 112 ′). And at least one wide section that allows relative axial movement between.本発明は、一般に、薬剤の複数の用量を選択および投薬する薬物送達デバイスを対象とする。薬物送達デバイスは、ハウジング（１０；１０’；１０’）に取り付けられた薬剤リザーバと、薬剤の用量を薬剤リザーバから投薬するためにハウジング（１０；１０’；１０’）に対して軸方向に可動であるプランジャ（３０；３０’）を含む駆動機構（３０、４０）と、駆動機構に解放可能に連結され、用量を選択するためにハウジング（１０；１０’；１０’）に対して第１の方向に回転可能である用量選択要素（６０、８０；６０’）と、用量選択要素（６０、８０；６０’）によって選択された用量の投薬を開始するためにハウジング（１０；１０’；１０’）に対して軸方向に可動であるトリガ（７０；
