Expandable collecting bag for an ostomy appliance

An expandable collecting bag for an ostomy appliance, the collecting bag comprising:

• a front wall and a rear wall;
• a base plate secured to the rear wall with a waste inlet opening formed in both of the base plate and the rear wall, with the rear wall attached to the front wall to form a cap portion and an expandable portion, the collecting bag is adapted to transition to an expanded configuration when waste is collected in the collecting bag;
• wherein the cap portion and the expandable portion combine to form a collecting cavity with a first inner surface of the front wall and a second inner surface of the rear wall forming an interior of the collecting cavity, and with a first outer surface of the front wall and a second outer surface of the rear wall facing outwards forming an exterior of the collecting bag;
• characterized in that the expandable portion has a sealed edge defined by the first outer surface of the front wall in direct attachment to the second outer surface of the rear wall, and characterized in that the cap portion has the first inner surface of the front wall in direct attachment to the second inner surface of the rear wall;
• wherein, in a non-expanded configuration, the expandable collecting bag has a discreet profile in which the sealed edge of the expandable portion is folded into a perimeter of the cap portion, and a stored thickness of the sealed edge located between the base plate and the front wall is limited to a thickness of the rear wall plus a thickness of the front wall.