Abstract: A one-piece, foldable mask and holding chamber for use with aerosolized medications includes a single flat patterned sheet of formable material that can be bent and folded to form a holding chamber, an integrated respiration mask, a one-way mask inlet valve having an attached valve membrane, and a one-way exhalation outlet valve having an attached valve membrane. The apparatus is configured to form a substantial seal around the nose and mouth of a patient such that the patient can inhale an aerosolized medication that has been introduced into the holding chamber by drawing the medication from the holding chamber, through the inlet valve to the interior of the mask, and into the lungs of the patient. The apparatus is formed by folding a series of segments of the flat pattern along various crease lines to create the holding chamber and mask, and then securing the segments in place with a series of retention tabs and tab engagement slots.