FIELD: medicine.
SUBSTANCE: group of inventions relates to medical equipment and relates to a hollow medical item, in particular a syringe or a carpule, and a piston for said hollow item. Hollow medical item, in particular a syringe or a carpule, comprising a piston that has at least one sliding surface for abutting against the hollow item, comprises at least one receiving area in which an antifriction means can be placed, and at least one releasing means for releasing at least one antifriction means from at least one receiving area onto at least one sliding surface. Receiving area is located in the piston. At least one releasing means is provided with at least one channel, which leads from at least one receiving area to at least one sliding surface, wherein the antifriction means may flow in the channel. In the first state of the piston, the antifriction means can not be released from at least one receiving area. In the second state of the piston, the antifriction means can be released by at least one releasing means to at least one sliding surface. Hollow item is further provided with a device by means of which pressure forces developed by the chemical reaction can be applied to the piston. Piston is provided with at least one membrane, which covers at least one receiving area in its upper region. Piston of said hollow medical item, in particular a syringe or a carpule, is arranged to move inside the hollow item along its longitudinal axis.
EFFECT: inventions provide a reduction in friction of the sliding surface of the piston against the inner surface of the hollow medical item, while preventing the pharmaceutical substance in the hollow item from coming into contact with the antifriction means and the resulting undesirable consequences.
9 cl, 9 dwg
