The Sound Science of Sonophoresis

As a general rule in life and skin care, if it sounds too good to be true, it most likely is. Too often our industry is replete with hype and hope in a jar with little evidence behind the statements. Even before and after pictures and articles can be subject, at times, to the magic of Photoshop and Artificial Intelligence (AI). We are focusing on how proven science, supported by a myriad of independent research, can lead to the application of an extremely efficacious technology that enhances the effectiveness of topical skin care.

The Science Behind Sonophoresis

Sonophoresis, also called phonophoresis, is a method that uses sound to enhance the effectiveness of topical products.^.1 Coupled with Iontophoresis, these two modalities create an extraordinary methodology of treatment results in aesthetic practice.²

The use of sound in therapeutics has gained increasing importance over the past 20 years.³ The use of energy to facilitate enhancement of topical products, in addition to expanding use in medical applications for transdermal drug delivery is common place today. For this article, we are focusing only on cosmetic uses that do not affect the form, function or structure of the body.

Sonophoresis is the use of ultrasound to drive molecules into or across the skin.⁴ When using the correct frequency of sound, it is non-invasive and painless. One of the leading pioneers in the use of sound in cosmetic applications is Sami Mitragotri.⁵ His research addresses the application of sound in not only cosmetic applications, but points to its future in transdermal delivery of pharmaceuticals. Des Fernandes, M.D., building on the work of Mitragotri, has written extensively on how to apply this technology to applications in topical skin care.^6,7

The mechanism of action related to sound is based on the principle of cavitation.⁸ Cavitation applies to the generation of and oscillation of gas bubbles, which facilitates the creation of microchannels on top of the skin to allow products to enter the stratum corneum. The frequency of sound determines the effect on our bodies. The essence of sonophoresis is ultrasound. But, not all ultrasound is equal, as the frequency can range from low levels (20 Hz up to three MHz) with corresponding effects on the permeability of skin. For sonohorsesis to work well, skin should be well hydrated. Lack of moisture impedes sound transfer and cavitation.

To begin to understand ultrasound, one needs to learn about its units of measurement called Hertz. Hertz is a measurement of cycles per second that sound produces. One hertz is one cycle per second. Therefore, 100 hertz is 100 cycles per second. A kilohertz (kHz) is 1,000 cycles per second, and a megahertz(MHz) is 1,000,000 per second.¹⁰ The more cycles, the faster sound travels. For its use on topical skin care applications, slower is better. Yet, most machines sold in the U.S. are one to three megahertz (MHz). Research at Massachusetts Institute of Technology, University of California, Santa Barbara and Ben Gurion University found that low frequency ultrasound yielded better results than high frequency.¹¹

Beware of Outlandish Claims

There are two major types of ultrasound in technology used in skin care devices: high frequency and low frequency. One cannot overstate the vast differences between the two. No matter what type is used, it is not a magical solution to enhancing cosmetic skin care treatments. One can pick up almost any publication and read about outlandish claims related to this technology. Just undertaking a cursory internet search, we found an ultrasound device from Asia that claims it is a multifunction ultrasonic body and skin care machine that smooths wrinkles, clears freckles and pouches under eyes, cleans skin and promotes weight loss.

Related: Why You Should Send Clients Home With Electro-Sonic Technology

Mechanism of Sonophoresis

Use of sonophoresis in your practice utilizes ultrasonic waves to enhance the effectiveness of topical products. This technology has been used in various forms of skin care treatments including the signs problematic skin, age related concerns and uneven skin tone.

The ultrasonic waves used in sonophoresis create a physical vibration in the skin, which causes microchannels to temporarily be created, allowing for better action from applied topicals. However, the delivery head of any ultrasound device has to be specially devised to allow it to remain on the skin for a period of time. This now allows these micro channels to be created without causing client discomfort or heating the skin which impedes the establishment of micro channels.

As an analogy, think of standing at the edge of a dock overlooking a calm pond, then dropping a large rock into the water. Watch as the waves radiate out from the source of impact. The sound interacts with the skin’s layers in a similar fashion; the waves create areas of compression and expansion. It is in those areas of expansion that opportunity exists.

Cavitation

Sonophoresis has been found to have several scientific mechanisms of action that contribute to its effectiveness. One of those processes, known as cavitation, where ultrasonic waves create tiny bubbles that implode, which then creates a mechanical pressure that pushes the topical ingredients to where the skin needs them.⁴ This increase in skin permeability is the main mechanism of action of sonophoresis. Hence, a scientifically proven benefit of sonophoresis is the ability to deliver essential ingredients to where the skin needs it most, allowing for more effective results.

Another benefit of sonophoresis is that it can be used in combination with other skin care treatments such as iontophoresis/galvanic, chemical peels and microdermabrasion to enhance their effectiveness. For example, sonophoresis can be used to deliver ingredients after a chemical peel or microdermabrasion treatment to make their results even more efficacious.

Medical Application

In addition to its cosmetic benefits, sonophoresis has been used in the medical field to enhance the penetration of drugs into the skin.^12,13 Sonophoresis has been used to deliver drugs such as lidocaine, which is used as a local anesthetic, and hydrocortisone, which is used to reduce inflammation in the skin. This ability to deliver drugs deeper into the skin has been found to be especially useful in the treatment of medical skin conditions such as eczema, psoriasis and atopic dermatitis.

Safety First

This process is non-invasive and painless, making it an attractive alternative to traditional methods of skin treatments such as needles or lasers, which have their own sets of dos and don’ts. Sonophoresis is a safe and well-tolerated procedure when performed by a trained and licensed skin care professional. Not all sonophoresis devices are created equal. The effectiveness of sonophoresis can vary depending on the specific device used, manufacturing standards and frequency.

The Science of Sound

Sonophoresis is a cutting-edge skin care treatment that utilizes ultrasonic waves to enhance the activity of ingredients. It is a non-invasive and painless alternative to advanced methods of skin treatment and can be used in combination with other skin care procedures to enhance their effectiveness. It is important to find a manufacturer and supplier that can offer dynamic training, a proven device backed by science, and a professional team of trainers to ensure you are educated on how best to use this cutting edge technology. Current innovations allow for portable, handheld devices for your clients to take this technology home to enhance your in-office treatments. Combined with effective product selection, sonophoresis can be a very valuable tool in providing and supporting on-going improvement of signs of the most common skin conditions.

Candace Noonan is a master trainer and director of education for DermaConcepts. She hosts trainings on the science of products and ingredients. She holds certificates for internationally recognized programs such as Advanced Skin Analysis, Dermal Needling and Oncology Esthetics, and is a frequent public speaker at medical and skin care conferences throughout the U.S.

Rob Trow has published more than 100 articles on skin care science and practical business solutions. Trow frequently speaks about topics of interest at national and international meetings, as well as to medical spas, estheticians and physicians. He can be reached at [email protected].