Self-contained disposable cryosurgical devices dispense a cryogenic fluid, such as a stream of liquid nitrous oxide, carbon dioxide or argon. The cryosurgical devices include a container, including a reservoir containing a cryogenic fluid, a flow passage configured to receive the cryogenic fluid from the reservoir, a valve assembly configured in an ergonomic housing, and a dispensing head. The device further includes at least one filter disposed in the flow passage configured to facilitate the flow of the cryogenic fluid. The valve assembly includes a valve body and valve slide that is actuated to effect the flow of the cryogenic fluid through the flow passage to patient target. The housing includes an activation lever with an eccentric hub that primes the device for use when a container is loaded into the housing and the activation lever is closed.