Disclosed herein is a fluid dispenser comprising a barrel defining a longitudinal axis terminating at a first fluid delivery end region； a body movable along the barrel relative to the first fluid delivery end region, the body including a needle carrier, a plunger and a capsule carrier therebetween, a latch interface between the body and the barrel and responsive to a release force therebetween caused by compressive engagement of the barrel at a fluid delivery site on a patient, to enable travel of the plunger and capsule carrier toward the needle carrier, to a dispensing configuration in which an upstream end of the needle pierces the capsule and projects form the first fluid delivery end region to deliver a fluid to the fluid delivery site.
