A top wall assembly to convert a shower enclosure into a therapeutic shower enclosure. The top wall assembly has an air blower in communication with one or more air return orifices in the top wall. An air distribution channel is in communication with the air blower and at least one air injecting orifice is provided in the top wall and communicates with the enclosure. A heater is provided in the air distribution channel for heating convected air therein to a temperature of up to about 75 C. to provide a stream of hot dry air circulating in the enclosure about a person's body standing therein whereby to cause the person's body to transpire and provide a therapeutic effect of shedding toxins through the skin. In combination with the hot dry air treatment there is available a chromotherapeutic and luminotherapeutic light treatment and an ion and ozone generator to inject ions and ozone in the hot dry air stream.