A medicament dispensing system comprising: a syringe having a cylindrical syringe body, which comprises at its lower end a base, comprising a pair of lugs extending laterally outwardly from said base, and a pair of substantially peripheral U shaped flanges which extend vertically from said base and which almost completely surround the cylindrical syringe body; a dispensing/suction pivot at the upper end of said syringe body, which extends vertically from a pivot base located at the center of said upper surface; said dispensing/suction pivot comprises a dispensing/suction conduit which extends inwardly through the pivot and the pivot base, and which is in fluid communication with an inner vacuum chamber of the syringe body; said syringe further comprises a piston or plunger which is formed by a plurality of vanes (28A, 28B, 28C, 28D) radially equidistantly separated from each other to form a single body, said piston comprises at its lower end a circular base and a portion wherein the vanes (28A, 28B, 28C, 28D) has a reduced height which is adjacent to said base, and at its upper end said piston comprises a circular piston head which has a diameter slightly greater than the inner diameter of the syringe body in the range of thousandths of a millimeter, and conical upper surface, said piston head further comprises at its outer edge a surface which is straight and smooth to a mirror-polished degree, so as to be in contact with the straight and smooth inner surface of the syringe body; the medicament dispensing system further comprises an inverted adapter which has a substantially cylindrical shape with a portion of its outer wall having a gradually reduced diameter to be inserted in a tight manner into a vial containing medicament; said adapter comprises an inverted cone which is disposed at the inner lower end of said adapter to promote the entire emptying of the medicament when said adapter is inserted in the vial; and a lip located at the outer upper end of said adapter, which serves as a stop to prevent that the adapter is fully inserted into the vial; wherein said through hole is adapted to receive said dispensing/suction pivot of the syringe so as to carry out the medicament suction; said system is characterized in that: the piston or plunger further comprises a segmented portion adjacent to said piston head, which comprises in each one of said plurality of vanes, a ridge, said ridges are located centrally over the length of said segmented portion of each vane, wherein the front ends or tips (36A, 36B, 36C, 36D) of said ridges coincide with the outer diameter of the piston head in order to form double support point to avoid the oscillation or pitching of said piston during the use of the system; and wherein said piston head does not require the use of a coating made of rubber, elastomeric or any other flexible material over the same to provide the vacuum effect into the vacuum chamber and to suction said medicament, and the adapter further comprises a through hole in the center thereof which is reinforced by a plurality of propeller shaped reinforcements (48A, 48B, 48C, 48D) radially disposed between said hole and said outer wall. the piston or plunger further comprises a segmented portion adjacent to said piston head, which comprises in each one of said plurality of vanes, a ridge, said ridges are located centrally over the length of said segmented portion of each vane, wherein the front ends or tips (36A, 36B, 36C, 36D) of said ridges coincide with the outer diameter of the piston head in order to form double support point to avoid the oscillation or pitching of said piston during the use of the system; and wherein said piston head does not require the use of a coating made of rubber, elastomeric or any other flexible material over the same to provide the vacuum effect into the vacuum chamber and to suction said medicament, and the adapter further comprises a through hole in the center thereof which is reinforced by a plurality of propeller shaped reinforcements (48A, 48B, 48C, 48D) radially disposed between said hole and said outer wall.