An ergonomic syringe includes a slide member, wherein force exerted on the slide member causes movement of a syringe plunger within a hollow or partially hollow syringe barrel, for withdrawing fluid from a source into the syringe, and also includes a reusable adaptor for use with existing conventional syringes, which has a ring that wholly or partially encircles the barrel and indirectly attaches to a plunger flange.