Abstract: An apparatus for the rapid delivery of therapeutic and or diagnostic agent to a body cavity or withdrawal of fluid from the body cavity is disclosed. This apparatus comprises in combination a catheter having a first and second conduit, an atomizer connected to the distal end of the first conduit, and a balloon surrounds the conduits. A multi-port valve is connected to the proximal end of the second conduit. An inflation tube with its input end connect to the multi-port valve while the output end connects to the balloon. A chamber for dispensing the selected agent is attached to one of the opening of multi-port valve via its air input while its output port is connected to the first conduit via a pressure relief membrane. A collection system having a three-way valve is connected to the opening of the multi-port valve by a third conduit.