Kybella is a unique medication that is relatively new to the marketplace of injectable cosmetic treatments since its FDA approval in 2015. It is indicated for the reduction of “submental fat,” which is the fat located at the front of the neck below the chin. Sometimes this accumulation of fat is also referred to as “submental fullness,” or “double chin.” This is a common condition that can give an individual the appearance of looking overweight, older, or less attractive than desired. Successful reduction of excess fat in this region creates a more defined jawline, a sharper angle between the neck and the skin under the chin (closer to a 90-degree angle), and more definition of the neck anatomy. Because other popular cosmetic injection treatments either relax muscle wrinkling (think Botox) or add volume to the face (think Restylane or Juvederm), it is easy to understand why Kybella is considered “unique” as the single FDA-approved medication devised to dissolve fat of the neck.
If one were to consider the stereotypical appearance of a fashion model who shows no visible fat along the front of the neck below the chin and an angle between the neck contour and jaw line close to 90 degrees (when viewed from the side), one could envision an “ideal” appearance for this area. Before the availability of Kybella, the options for correcting submental fat were limited to other alternatives such as liposuction or incisional surgery. While there is no single approach that is optimal for everyone, a plastic surgeon can help decide what would be best in each individual case. Some of the factors that need to be considered in thinking about the options include the speed of getting results, the overall costs, one’s general medical condition and health status, and the quantity of fat needing reduction. Because the plastic surgeon has expertise with liposuction as well as the non-surgical procedures, he or she is ideally suited to guide this decision process.
For decades, practitioners have offered treatments called “mesotherapy,” which refers to the process of reducing subcutaneous fat by injecting a variety agents into areas with the intention of trying to contour and shape those areas. These procedures are considered controversial by many, in that the chemicals injected and the precise control of the results are not part of an established protocol that has been experimentally determined to be safe or effective. Apart from the issue of safety, the use of mesotherapy has caused incidences of contour irregularities after treatment, such as indents or irregularities of skin smoothness. To many board-certified plastic surgeons, mesotherapy has been considered somewhat “sketchy” in nature, and many of us have evaluated patients who had problems after mesotherapy for which they ultimately found themselves in a plastic surgeon’s office. The FDA approval of Kybella places this agent in a different class, since there are significant scientific requirements that must be met before it can be used in the U.S.
Kybella is manufactured and shipped as a sterile liquid comprised of deoxycholic acid. This type of acid is naturally found in the bile of our intestinal tract where it acts to help absorb fats. When this fluid is injected into an area of excess fat, it causes the destruction of the cells that store fat (called “adipocytes”) by disrupting the cell membrane. Once destroyed, these cells no longer accumulate fat in the treated area, and fat is not expected to return under ordinary circumstances. A treatment session is relatively easy, and involves a few basic steps. While most people are safe candidates for treatment, patients on major blood thinners or those with any infection or inflammation at the anticipated injection sites are not advised to be treated. Patients should ensure their skin is clean and free of makeup as well as any topical creams immediately before the session. Once a candidate is ready to move forward, the treating physician may apply some markings or a grid to the neck skin to serve as a “guide” to the specific injection sites. The dose of the Kybella, which is essentially the volume to be injected, is planned based upon the size of the area to be treated, and it is prepared in syringes by the doctor. There is some moderate discomfort associated with injecting Kybella, and this can be reduced by a number of techniques including use of topical numbing cream, injections of local anesthetic given prior to the Kybella, use of topical ice, or a combination of these. Finally, the Kybella is injected based upon the skin markings and the neck anatomy. Although the medication is injected into specific spots using a very tiny needle, it will spread over a very small distance from each spot and help create a more even reduction in the contour by this small spreading effect. The entire treatment session can span as little as 10 minutes or so, unless a patient also receives a local anesthetic. While the aftercare is not demanding, patients should be advised that both swelling and pain will be present for a few days at the treatment site. There may also be visible bruising, redness, numbness and/or firmness in the areas injected. In this post-treatment phase, use of over-the-counter medications for comfort is often recommended. Most commonly, my patients briefly use ibuprofen. After a few days, the swelling subsides, and then the reduction of fat gradually occurs over a period of weeks. Follow-up treatment should be given at least 4 – 8 weeks after the last treatment session.
As with almost all cosmetic treatments, the details should be customized to the individual and this includes decisions about the dosing of a given session as well as the total number of treatment sessions needed to reach the desired end point. Most treatment sessions do not typically exceed two vials, or 4cc volume, and most patients can complete their treatment program in no more than four treatment sessions (often less). Side effects of the treatment vary in incidence, and are generally mild. The most common side effects are swelling, pain, redness, firmness, bruising, and numbness. The uncommon side effects that have been reported include nerve injury (4%) and difficulty swallowing (2%). In the hands of the qualified plastic surgeon with knowledge of the anatomy, including the location of specific nerves, this risk should be very low.
One of the major alternatives to Kybella is the option of submental liposuction. This is a procedure with a reliable track record of effectiveness that can be performed in one session through the use of tiny incisions that ultimately have minimal or no visibility. Liposuction employs the use of small metal tubes (called “cannulas”) that allow fat to be suctioned out by the same principle that fluid is drawn through a straw by suction effect. Even though the cannulas are inserted using tiny incisions, it is possible to remove fat from a large area because the cannulas are fairly long and allow all of the areas to be reached. Liposuction has the advantage of allowing all of the fat to be removed in one treatment, and the amount removed can be controlled with precision. With this approach, “what you see is what you get,” and the removed fat can be documented rather than waiting for fat to dissolve over a period of weeks. If liposuction is to be performed only in the neck area, it can be handled under local anesthesia unless a patient prefers to sleep during the short procedure. In comparing liposuction to Kybella in the neck, one can generalize that the advantages of Kybella include: (1) Minimal preparation to get ready for the treatment; (2) Lower cost if the amount of Kybella for all treatments required is lower volume; (3) Less bruising than surgery for many people; (4) Possibly better suitability for patients with medical problems or those who cannot easily lie flat on an operating table; and (5) Virtually no down time for most people (depending upon one’s work). On the other hand, advantages of liposuction include: (1) One treatment session to remove the excess fat in most instances (this is the key advantage); and (2) Possibly lower cost when compared to multiple Kybella sessions of high volume, depending on the total cost of the Kybella. In addition to liposuction, some patients benefit from direct surgery in which the fat is reduced and the platysma neck muscle is tightened at the same time. Evaluating the laxity of the neck muscles is an important part of a consultation, and a plastic surgeon can inform a prospective candidate about his or her neck muscle situation and how it relates to choosing the right therapy.
Given the success of Kybella for double chin, many people have expressed the desire to have Kybella injected into other areas of the body. At this time, however, its use outside the submental region has not been established or recommended.