Retractable needle adapters and safety syringes

A barrel adapter for a safety syringe having a barrel and a plunger assembly adapted to move within the barrel, the adapter comprising:

• a barrel tip adapted to be sealingly engaged with a distal end of the barrel,
• a needle retraction mechanism including
• a needle subassembly including
• a needle, and
• a needle-over-mold through which the needle extends,
• the needle subassembly being disposed at least partially within the barrel tip and adapted to move from an injection position in which the needle extends from a distal end of the barrel tip to a retracted position in which the needle is disposed within at least one of the barrel tip or the barrel,
• an actuator subassembly including
• a needle seal, the
• a push bar, and
• at least one actuating surface,
• the push bar being disposed at least partially proximal the needle seal at least one biasing member, and
• an actuable locking arrangement disposed to maintain the biasing member in
• an energized position when the locking arrangement is locked and release the biasing member when actuated, the biasing member being disposed to move the needle from the injection position to the retracted position when the biasing member is released from the energized position, the locking arrangement being actuable by depression of the plunger assembly and contact of the plunger assembly with the push bar.