Ultrasound in percutaneous absorption

Kost, J. 1989. Ultrasound as a Transdermal Enhancer. In Percutaneous absorption, ed. Maibach, H. I, 595. New York and Basel Marcel Dekker. 

Kost, J. Levy, D. Langer, R. Ultrasound as a transdermal enhancer. In Percutaneous Absorption Mechanisms-Methodology-Drug Delivery, Bronaugh, R., Maibach, H.I., Eds. Marcel Dekker, Inc. New York, 1989 595-601. 

Fang, J.Y., et al. 1999. Effect of low frequency ultrasound on the in vitro percutaneous absorption of clobetasol 17-propionate. Int J Pharm 191 33. 

The use of ultrasound (US) to enhance percutaneous absorption (so-called sonophoresis or phonophoresis) has been studied over many years, and is the basis of US propagation and US effects on tissue, and the use of US in transdermal delivery have been reviewed in detail. The proposed mechanisms by which US enhances skin penetration include cavitation, thermal effects and mechanical perturbation of the SC that is, US acts on the barrier function of the membrane. ... 

Topical applications in the form of spray also have been reported as vehicles for enhanced frawi-dermal delivery of drugs such as testosterone, estradiol, progesterone, and norethindrone acetate. More effective drug penetration was reported with enhancers padimate and octyl salicylate and compared with laurocapram and oleic acid (38). Other methods reported for enhanced percutaneous drug absorption include iontophoresis (39), ultrasound or sonophoresis (40), and electroporation (41). 

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