Abstract: A pneumatic action dispenser for filling bottles with soda and carbon dioxide according to alternate mixing sequences, where each bottle has a normally closed closure valve in its neck, said dispenser being engageable with the neck of the bottle and provided with a pneumatically and coaxially activated mobile body which contains another body mobile with respect to the other, said second mobile body having a mouthpiece engageable with the bottle which is provided with a central opening for a member capable of opening the valvular closure of the bottle and which is in communication with an inlet and/or outlet connector for carbon dioxide and soda. The main pneumatically activated mobile body includes a member for opening the valvular closure of the bottle, the activation of which opens a closure valve within the dispenser between the main and second mobile bodies in the communication line for the fluid feed.