A autoinjector type syringe apparatus is provided for injecting a liquid medicine or like into a patient. The apparatus includes a housing that is of two parts including a transversely extending upper housing and a downwardly extending vertically oriented lower housing. A syringe barrel is supported by the housing and has an interior for holding a liquid medicament for being dispensed. A piston is slidably disposed within the interior of the syringe barrel for injecting the medicament from the barrel, the piston being movable between retracting and dispensing positions. A cam member supported by the housing for operating the piston to move between retractive and dispensing positions, the cam being movable between loaded and dispensing positions. The housing includes an upper transversely extending section with an external surface and a cocking mechanism that includes an externally positioned handle that slides on the outer surface of the upper portion of the housing. The handle has a connection with the cam so that when the handle slides upon the upper section, the cam can be cocked into the loaded position. A trigger mechanism releases the cam when the cam is in the loaded position and the trigger is depressed by the user. Springs can be used to bias the cam toward the dispensing position, the springs being stretched when the handle is moved into the cocked position prior to use.