Abstract: A device for the simultaneous delivery of beta 2 agonists and oxygen to a patient. This device comprises a main chamber, an adaptor at one end of the chamber to accomodate a metered dose inhaler, and a mask or mouthpiece detachably mounted at the other end of the main chamber. A tube of given length is connected to and in open communication with the main chamber at one end, and open to air at the other end. A unidirectional valve is placed in the tube at a short distance from the end connected to the main chamber mounted in such a manner as to allow flow circulation within the tube towards the main chamber exclusively. An auxiliary tube is connected to and in open communication with the tube at one end, at a given distance from the unidirectional valve away from the main chamber. The other end of this auxiliary tube is devised to accomodate an oxygen source.