A dispenser has a body with a variable-volume storage chamber for storing substance, and a dispensing portion defining a dosage chamber in fluid communication with the storage chamber. A first valve includes a valve seat and a flexible valve cover seated thereon defining a normally-closed fluid-tight seam therebetween. The valve cover relative to moves from the valve seat to allow substance through the seam and out of the dispenser. A second valve allows substance from the storage chamber into the dosage chamber and substantially prevents flow from the dosage chamber into the storage chamber. An actuator is manually movable between (i) a first non-actuated position, and (ii) a second actuated position extending into the dosage chamber for compressing a dose of substance therein, dispensing substance through the first valve. The elasticity of the actuator causes it to return to the first non-actuated position upon manually releasing the actuator.