A first and second housing joined together and rotatable with respect to
each other, each housing having a conduit integral with an exterior wall,
the conduits each having passageways leading to an internal portion of the
respective housings. An internal edge of each housing mounts a
heat-moisture exchange material having a transverse opening axially
aligned with the passageway of the closest conduit. The passageway in the
respective conduits are offset permitting passage of air to and from the
patient through the heat-moisture material. The housings are rotated with
respect to each other to axially align the passageways in the two conduits
to permit passage of aerosol medicine through the exchanger without
passing through the heat-moisture material.
