An injection device comprises an acoustic sensor configured to detect environmental acoustic signals; an acoustic signal generator operable to generate an acoustic signal; and a controller configured to control the acoustic signal generator to generate an alert having acoustic properties that are selected based on the detected environmental acoustic signals. A feedback system comprises: a first device comprising an acoustic signal generator operable to generate an acoustic signal; and a second device comprising an acoustic sensor configured to detect environmental acoustic signals, and a controller configured to control the acoustic signal generator of the first device to generate an alert having acoustic properties that are selected based on the detected environmental acoustic signals and one of the first device and the second device is an injection device, and the other one of the first device and the second device is a mobile device or a controller device.

A plunger assembly (100) for use with an auto-injector and comprising: a cartridge (102); and a firing assembly (103) comprising a plunger rod (104) and a drive portion (105), the firing assembly (103) being axially moveable relative to the cartridge (102), wherein the firing assembly (103) is configured to couple to the cartridge (102) at a coupling point along a length of the cartridge (102) to fix an axial position of the drive portion (105) relative to the cartridge (102), and wherein the length of the cartridge (102) is configured to be extended in a rearward direction such that the coupling point and a forward end (106) of the plunger rod (104) move rearwards.

A plunger assembly (100) for use with an auto-injector and comprising: a cartridge (102); and a firing assembly (103) comprising a plunger rod (104) and a drive portion (105), the firing assembly (103) being axially moveable relative to the cartridge (102), wherein the firing assembly (103) is configured to couple to the cartridge (102) at a coupling point along a length of the cartridge (102) to fix an axial position of the drive portion (105) relative to the cartridge (102), and wherein the length of the cartridge (102) is configured to be extended in a rearward direction such that the coupling point and a forward end (106) of the plunger rod (104) move rearwards.

An apparatus (100) for use with an auto-injector configured to receive a syringe and comprising: a firing assembly (102) comprising a rearward portion (108), a plunger rod (110) moveable forward relative to the rearward portion (108) and a plunger rod driver (112) configured to drive the plunger rod (110) forward relative to the rearward portion (108); an insertion driver (106) configured to drive the syringe forwards on an insertion stroke for inserting a needle of the syringe into an injection site; and wherein the firing assembly (102) further comprises a retainer (114) engaged with the plunger rod (110) and/or the rearward portion (108) and configured to prevent forward movement of the plunger rod (110) relative to the rearward portion (108), and to disengage from the firing assembly (102) at a point on the insertion stroke.

An apparatus (100) for use with an auto-injector configured to receive a syringe and comprising: a firing assembly (102) comprising a rearward portion (108), a plunger rod (110) moveable forward relative to the rearward portion (108) and a plunger rod driver (112) configured to drive the plunger rod (110) forward relative to the rearward portion (108); an insertion driver (106) configured to drive the syringe forwards on an insertion stroke for inserting a needle of the syringe into an injection site; and wherein the firing assembly (102) further comprises a retainer (114) engaged with the plunger rod (110) and/or the rearward portion (108) and configured to prevent forward movement of the plunger rod (110) relative to the rearward portion (108), and to disengage from the firing assembly (102) at a point on the insertion stroke.

A medicine injection pen includes a rotatable drive member and a rotary encoder associated with the drive member. The rotary encoder is configured to determine an amount of liquid medicine dispensed based on a rotational orientation of the drive member.

A medicine injection pen includes a rotatable drive member and a rotary encoder associated with the drive member. The rotary encoder is configured to determine an amount of liquid medicine dispensed based on a rotational orientation of the drive member.

A torque-limiting device comprises a plunger rod holder defining a piston cavity for receiving at least a portion of a plunger rod, a moveable stop element, a dowel disposed adjacent the stop element, a spring disposed adjacent the dowel, and a syringe barrel holder defining a barrel cavity for receiving at least a portion of a syringe barrel.

A device for administering needle-free subcutaneous treatment to a patient comprises an actuator configured to deliver a plurality of volumes of a treatment at a plurality of locations on a body of the patient; at least one imaging device configured to detect a movement of the needle-free device from a first location on the body of the patient to a second location on the body of the patient; and a processor configured to determine the second location on the body of the device relative to the first location from the movement of the needle-free device relative to the first location on the body, the processor further configured to determine a volume of the plurality of volumes of the treatment to deliver to the body of the patient at the second location.

This disclosure relates to features of an injection device arranged to provide a sensory distraction to a user during insertion of a needle into flesh. According to a first aspect, an injector device includes a housing having a proximal end and a distal end, and configured to receive a container of medicament, a needle housing for holding a needle in a position at the distal end of the housing, and a needle sleeve mounted within the housing, wherein the needle sleeve and needle housing are moveable relative to one another by a user action between a first configuration in which the needle sleeve would enclose a needle, and a second configuration in which a needle would extend from the needle sleeve in the distal direction, wherein the needle sleeve comprises a portion configured to vibrate and/or rotate during motion between the first configuration and the second configuration.