A method of treating areas of the body utilizing ultrasonic vibrations to mix different materials together as to create a therapeutic combination is disclosed. The materials are mixed by passing them through an ultrasound horn vibrating in resonance, having an internal chamber. As the materials pass through the internal chamber, ultrasonic vibrations emanating from and/or echoing off the various walls of the chamber mix the materials into a potentially therapeutic combination. Ultrasonic vibrations emanating from the radiation surface of the horn may be used to spray the created therapeutic combination onto the area of the body to be treated.