A medicinal foam producing device comprising a gas vessel (46) to hold a sterile gas； an active agent vessel (48) to hold an active agent； a connecting element (10) to connect the vessels； and two feed elements for respectively feeding the gas and active-agent back and forth between the vessels to produce a medicinal foam, is new. A medicinal foam producing device comprising a gas vessel (46) to hold a sterile gas； an active agent vessel (48) to hold an active agent； a connecting element (10) to connect the vessels； and two feed elements for respectively feeding the gas and active-agent back and forth between the vessels to produce a medicinal foam, is new. The connecting element is connected with one of the vessels, preferably gas vessel, and comprises a closure element (34) for sterile closure of the vessel. The closure element can be automatically opened by connecting the connecting element with the other vessel, preferably the active agent vessel. The opening is effected by penetrating a membrane (42) provided in the closure element. The connecting element comprises a tube (20) which penetrates the membrane when the two vessels are connected. The closure element in connected state, permits flow of the active agent and the gas through the tube, and in the unconnected state, prevents intrusion and escape of gas and/or liquid into or from the vessel. The closure element comprises a resilient plastics stopper or a slit to be opened. The closure element is preferably spring-loaded. The vessels are in the form of syringes, and the feed elements are syringe pistons. Independent claims are included for: (1) the gas vessel filled with gas and closed by the connecting element having the closure element； and (2) a kit for producing the medicinal foam.
