[Application of ultrasound energy as a new drug delivery system]

Ultrasound is frequently used in medicine for diagnostic purposes. Recently, there have been numerous reports on application of ultrasound energy for controlling drug release or targeting. This new concept of therapeutic ultrasound combined with drugs has induced excitement in various areas. Ultrasound energy can enhance effects of thrombolytic agents as urokinase. Ultrasound emitting catheters are currently being developed for cardiovascular diseases. Device with ultrasound transducers implanted in transdermal drug patches are also being evaluated for possible delivery of insulin through the skin. Chemical activation of drugs by ultrasound energy for treatment of cancers is another new field recently termed as "Sonodynamic Therapy". Various examples of application of ultrasound for drug delivery systems are discussed.