We are so lucky to be part of a field of medicine where advances in patient treatment options continue to occur. Having been involved in the Kybella clinical trials, it is exciting and satisfactory to see a new successful aesthetic treatment come to fruition. Kybella is the first and only Food and Drug Administration–approved injectable drug to reduce the appearance of “double chin” (submental fullness associated with submental fat) in adult patients. It is a synthetic form of naturally occurring deoxycholic acid (DCA), which lyses adipocytes when properly injected into subcutaneous fat. The safe and effective use of Kybella for the treatment of subcutaneous fat outside of the submental region has not been established and is not recommended.
The drug received unanimous support from an FDA advisory panel in March based on two placebo-controlled phase III trials involving more than 1,000 adults. In over 1,600 patients treated, 79% saw great improvement. In the studies, safety and efficacy were demonstrated with treatment of up to 50 injections of 0.2 mL each of the 1% DCA solution administered in a single treatment. Up to six treatments were administered at least 1 month apart.
Serious side effects associated with injection of DCA may include injury to the marginal mandibular nerve and dysphagia, but the most common side effects are swelling, bruising, pain, numbness, redness, and areas of hardness in the treatment area. Other potential side effects include: tingling, nodule, itching, skin tightness, headache, alopecia, and skin ulceration. In the studies, all cases of marginal mandibular nerve injury, manifesting as an asymmetric smile or facial muscle weakness, resolved spontaneously (range 1-298 days, median 44 days). Dysphagia occurred in the clinical trials as a result of administration site reactions (for example, pain, swelling, and induration in the submental area). Cases of dysphagia resolved spontaneously (range 1-81 days, median 3 days).
Caution should be taken in patients with a history of medical conditions in the neck area, difficulty swallowing, bleeding problems, or who take blood thinners. Likewise, caution should be used in patients who are or plan to become pregnant or breastfeed as Kybella has not been studied in pregnant or breastfeeding patients. Injection is contraindicated in the presence of infection at injection sites. Kybella only should be administered by a trained health care professional.
In addition to assessing whether not the patient is an ideal candidate, setting realistic expectations, and counseling about potential side effects, consultation also should include preprocedure photographs in the Frankfurt plane. Patients with moderate to severe convexity or fullness of the submental area are ideal candidates for the procedure. Those with little submental fat and excessive skin laxity may not be good candidates for this procedure and should consider a neck lift surgery as an alternative. Patients with prominent platysmal bands prior to procedure still may notice these bands after the procedure and may consider botulinum toxin injections or platysmal banding to treat these. While the active ingredient targets fat, some beneficial skin tightening may occur as a result of inflammation and fibrosis.
After photographs are taken, it is highly recommended to mark out specific anatomic landmarks on the patient, to avoid injury to the marginal mandibular nerve, salivary glands, lymph nodes, and the subhyoid region.
The procedure takes about 15-20 minutes with a short preparation time involved. Antihistamines and anti-inflammatory medications such as loratadine and ibuprofen may be given before the procedure to help reduce risk of discomfort and edema often experienced after injection. Preprocedure injection with local anesthetic also is recommended.
Once the treatment area is demarcated with a grid placed on the patient’s skin, injections of 0.2 mL of DCA are performed with a 30-gauge ½ inch needle. The product is supplied in a box with four 2-mL vials (10 mg/mL). No refrigeration is required. Once a vial is opened, it should only be used on one patient. A maximum of up to 10 mL may be injected in one patient in one session. Ice may applied after treatment. Postprocedure swelling and throbbing can be expected for several days and may rarely last up to 1 month. Patients may require two to six treatments spaced at least 1 month apart.
Dr. Wesley and Dr. Talakoub are cocontributors to a monthly Aesthetic Dermatology column in Dermatology News. Dr. Talakoub is in private practice in McLean, Va. Dr. Wesley practices dermatology in Beverly Hills, Calif. This month’s column is by Dr. Wesley. Dr. Wesley was an investigator in the phase III Kybella clinical trials. E-mail her at dermnews@frontlinemedcom.com.