A metering pump, comprising: - a chamber having a proximal portion and a distal portion; - a piston (104; 504; 604) accommodated in the chamber (102; 502; 602) and being movable in the chamber (102; 502; 602); - a drive for driving the piston (104; 504; 604) reciprocally form a proximal dead center to a distal dead center in the chamber, wherein the distal dead center is located at the distal portion of the chamber and the proximal dead center is located at the proximal portion of the chamber; - an outlet valve (116; 516; 616) located adjacent to the distal portion of the chamber, wherein the outlet valve (116; 516; 616) allows a flow of fluid from the chamber, if the piston (104; 504; 604) is moved in the distal direction, and blocks a fluid flow into the chamber, if the piston (104; 504; 604) is moved into the proximal direction; - a seal (122; 522; 622') located at the distal portion of the chamber, wherein the seal (122; 522; 622') seals the chamber, if the piston (104; 504; 604) is positioned at the distal dead center and contacts the seal (122; 522; 622'), wherein the seal (122; 522; 622') is located at the distal dead center position of the piston (104; 504; 604) and wherein the distal portion of the piston (104; 504; 604) compresses the seal (122; 522; 622') elastically in the distal dead center position of the piston (104; 504; 604); and - an inlet valve (114; 514; 614), wherein the inlet valve (114; 514; 614) allows a flow of fluid into the chamber, if the piston (104; 504; 604) is moved in the proximal direction, and blocks a fluid flow out of the chamber, if the piston (104; 504; 604) is moved in the distal direction. - a chamber having a proximal portion and a distal portion; - a piston (104; 504; 604) accommodated in the chamber (102; 502; 602) and being movable in the chamber (102; 502; 602); - a drive for driving the piston (104; 504; 604) reciprocally form a proximal dead center to a distal dead center in the chamber, wherein the distal dead center is located at the distal portion of the chamber and the proximal dead center is located at the proximal portion of the chamber; - an outlet valve (116; 516; 616) located adjacent to the distal portion of the chamber, wherein the outlet valve (116; 516; 616) allows a flow of fluid from the chamber, if the piston (104; 504; 604) is moved in the distal direction, and blocks a fluid flow into the chamber, if the piston (104; 504; 604) is moved into the proximal direction; - a seal (122; 522; 622') located at the distal portion of the chamber, wherein the seal (122; 522; 622') seals the chamber, if the piston (104; 504; 604) is positioned at the distal dead center and contacts the seal (122; 522; 622'), wherein the seal (122; 522; 622') is located at the distal dead center position of the piston (104; 504; 604) and wherein the distal portion of the piston (104; 504; 604) compresses the seal (122; 522; 622') elastically in the distal dead center position of the piston (104; 504; 604); and - an inlet valve (114; 514; 614), wherein the inlet valve (114; 514; 614) allows a flow of fluid into the chamber, if the piston (104; 504; 604) is moved in the proximal direction, and blocks a fluid flow out of the chamber, if the piston (104; 504; 604) is moved in the distal direction.