Non-reusable medical needle apparatus

A non-reusable syringe for injecting fluid, said syringe comprising:

• a barrell with elongated cavity therein, said barrel having an open end and a relatively closed end,
• a hollow needle projecting from the closed end of the barrel, said needle being in fluid flow communication with the elongated cavity,
• plunger fitting into the open end of the barrel and having an end projecting outwardly therefrom, said plunger having a lateral dimension enabling plunger withdrawal once for filling the barrel with fluid,
• means for restraining the barrel with two fingers of one hand while applying thumb pressure with the same hand to the outwardly projecting plunger end in a direction towards the barrel,
• means responsive to thumb pressure on the plunger for injecting fluid, and
• integrally molded plastic means that deforms in response to thumb pressure on the plunger for increasing the lateral dimension of the plunger to interlock with the barrel thereby preventing secondary plunger withdrawal and rendering the syringe non-reusable after fluid injection.

A non-reusable syringe for injecting fluid, said syringe comprising:

• a barrel with an elongated cavity therein, said barrel having an open end and a relatively closed end,
• a hollow needle projecting from the closed end of the barrel, said needle being in fluid flow communication with the elongated cavity,
• a plunger fitting into the open end of the barrel and having an end projecting outwardly therefrom, said plunger having a lateral dimension enabling plunger withdrawal once for filling the barrel with fluid,
• means for restraining the barrel with two fingers of one hand while applying thumb pressure with the same hand to the outwardly projecting plunger end in a direction towards the barrel,
• means responsive to thumb pressure on the plunger for injecting fluid, and
• plastic deformable means responsive to thumb pressure on the plunger for increasing the lateral dimension of the plunger to interlock with the barrel and thereby render the syringe non-reusable after fluid injection by preventing secondary plunger withdrawal, said plastic deformable means being formed by two plunger portions interconnected by integrally molded flexible straps that bend in compression during injection so that the two plunger portions can interlock and wedge within the barrel.