A drug delivery device for selecting and dispensing a number of user variable doses of a medicament includes a housing having a tubular portion with an inner thread, a piston rod having a threaded portion and a distal end, and a bearing having a distal face and a proximal face. The bearing includes a retaining stem protruding from the proximal face. The piston rod includes a distal portion having an outer diameter which is smaller than the inner diameter of the inner thread of the tubular portion and comprising at its distal end at least one retaining clip engaging the retaining stem. The axial length of the tubular portion is smaller than or equal to the axial distance between the proximal face of the bearing disc and the distal end of the threaded portion of the piston rod. During manufacturing of the device, the retaining clip engages the retaining stem prior to the inner thread of the tubular portion engages with the threaded portion of the piston rod.

A plunger rod for use with a syringe barrel includes a first flange adjacent a distal end of the plunger rod, a second flange adjacent a proximal end of the plunger rod opposite the distal end, and a securing flange between the first flange and the second flange. The securing flange is configured to prevent movement of the plunger rod in a proximal direction beyond a predetermined position when the plunger rod is disposed within the syringe barrel. A syringe assembly and a method of preparing a syringe assembly are also disclosed.

A plunger rod for use in a syringe barrel for driving a bung through the syringe barrel to expel a substance therefrom, the plunger rod including: a bung fixing configured to be received within a recess of a bung and including at least one laterally extending lug including a thread engagement surface configured to engage with a point on a track portion of a thread on a sidewall of the recess, wherein the lug is further configured to cross the thread on relative rotation between the plunger rod and the bung under a force applied by a user, such that the thread engagement surface of the lug engages the point of the track portion every full rotation of the syringe plunger relative to the bung.

A container for storing and mixing two components is provided. The container includes a body, a first plug, and a second plug. The body has a first end, a second end, and a bypass with a length L disposed between the first and second ends. The first and second plugs are slidably disposed in the body and define a first compartment. A second compartment is in the body between the second plug and the second end. The second plug has a first edge, a second edge, and a primary conduit extending therein, a plurality of secondary conduits extending from the primary conduit through the second plug. The primary conduit has a first opening. A distance D extends longitudinally from the first edge to the second edge and a distance E extends longitudinally from the first edge to the first opening. DL and E<L.

An I.V. flush syringe assembly includes a barrel having an inside surface defining a chamber for retaining fluid, an open proximal end and a distal end with a passageway therethrough in fluid communication with the chamber. An elongate plunger having a proximal end, a distal end and a flexible stopper is slidably positioned in fluid-tight engagement with the inside surface of the barrel for drawing fluid into and out of the chamber by movement of the stopper relative to the barrel. The barrel includes anti-reflux structure for holding said stopper in a partially deflected position after fluid has been delivered from the chamber and the stopper is being force against the distal end of the chamber.

An anti-back mechanism for a drug delivery device according to the present application includes a retaining groove, a position retaining protrusion and a clamping groove. The retaining groove is provided on a push rod. The position retaining protrusion is provided in the drug delivery device. The clamping groove has an accommodation cavity into which the position retaining protrusion is inserted. The position retaining protrusion is provided on a ring having a notch and may be clamped with respect to the push rod when the position retaining protrusion is squeezed. When the position retaining protrusion is subjected to a reverse thrust from a cartridge holder of the drug delivery device, the position retaining protrusion may move in a direction opposite to an injection direction, be inserted into the clamping groove to be clamped, and be hooked to the retaining groove to be locked.

A stopper adapted for attachment with a plunger rod for use within a syringe barrel is disclosed. The stopper includes a main body defining an open rearward end and a closed front end. The open rearward end is adapted to receive a front forward end attachment portion of the plunger rod. The stopper also includes a core member integrally formed with the main body adjacent the closed front end. The core member includes a nose portion having a conical tip configured for entering an outlet opening of the syringe barrel. The closed front end of the stopper has a profile configured to cooperate with an internal surface of the syringe barrel wall to prevent reflux and reduce dead space within the barrel.

An I.V. flush syringe assembly includes a barrel having an inside surface defining a chamber for retaining fluid, an open proximal end and a distal end with a passageway therethrough in fluid communication with the chamber. An elongate plunger having a proximal end, a distal end and a flexible stopper is slidably positioned in fluid-tight engagement with the inside surface of the barrel for drawing fluid into and out of the chamber by movement of the stopper relative to the barrel. The barrel includes anti-reflux structure for holding said stopper in a partially deflected position after fluid has been delivered from the chamber and the stopper is being force against the distal end of the chamber.

Embodiments of the invention are directed to flush syringe assemblies comprising an integrated contamination-prevention device integrated with device connector flushing positioned so that the practitioner cannot forget to apply disinfectant. The flush syringe assemblies comprise a barrel with an elongate plunger rod disposed therein and a cap comprising a passageway. The plunger rod includes a stopper of which at least a portion can be embedded in the passageway of the cap to form a plug in the cap.

A medicament delivery device for a disposable container having at least one chamber for a liquid medicament encapsulated in the container by at least one movable plunger. The medicament delivery device is elongated along a longitudinal axis (A), has proximal and distal ends, and includes a housing with proximal housing section configured for accommodating the disposable container and a distal housing section; a plunger rod configured for contacting the movable plunger; and a drive mechanism arranged in the distal housing section for applying, when the medicament delivery device is activated, a force on the movable plunger in a proximal direction via the plunger rod. The plunger rod includes an outer periphery having at least two axially separated recesses or cut-out portions for retaining liquid medicament that leaks along the plunger rod toward the drive mechanism.