The invention concerns a medication inhaler (1) for aerosol therapy according to a patient, especially a paediatric patient, comprising a housing (2), a top cover (5) fixed to the housing (2) and an inner compartment (6) arranged between said housing (2) and said top cover (5). The housing (2) comprises a hollow chamber (3) with an exit orifice (4), and the top cover (5) comprises an outlet (7), said exit orifice (4) of the hollow chamber (3) and said outlet (7) of the top cover (5) being in fluid communication with the inner compartment (6). A venting channel (9) comprising an entry port (9a) and a venting port (9b), is in fluid communication with the inner compartment (6) via the entry port (9a) and further with the atmosphere via the venting port (9b). A one-way valve (8) is arranged in the inner compartment (6). According to the invention, the venting channel (9) comprises visual feedback system comprising a mobile element (10) that moves into said venting channel (9) in the direction of the venting port (9b), when the patient exhales gas through the outlet (7) of the top cover (5). Aerosoltherapy assembly comprising such a medication inhaler and an aerosol drug delivery (ADD) device plugged into it.
