An injection device a barrel having a proximal end for a needle to protrude therefrom a needle assembly having a double-pointed hollow needle and a biasing means operable to bias the double-pointed hollow needle away from the proximal end of the barrel a cartridge and a mechanism operable to cause the cartridge to be punctured by the first end of the needle, and to cause the second end of the needle to protrude from the proximal end of the barrel and to be locked in the protruded position.一種注射裝置,包括:一外筒,具有一近端供一針頭突伸;一針頭總成,具有一個兩頭尖的中空針頭和一個偏置裝置,偏置裝置可操作以將兩頭尖的中空針頭偏置遠離外筒的近端;一藥劑筒;及一機構,其可操作使藥劑筒被針頭的第一端刺穿,並使針頭的第二端從藥劑筒的近端突出及被鎖定在突出位置。10‧‧‧注射裝置12‧‧‧外筒16b‧‧‧第二部分18‧‧‧內筒20‧‧‧藥劑筒24‧‧‧針頭
