Kybella is the first and only FDA approved injectable drug that reduces fat and clinically improves the appearance of submental (beneath the chin) fullness. Kybella is deoxycholic acid and is identical to the deoxycholic acid that is produced in the body. Deoxycholic acid produced in the body is a bile acid secreted by the liver. The acid causes adipocytolysis, which is the rupture of the fat cells leading to reabsorption in the body. When the fat cell is exposed to the deoxycholic acid properly, the fat cell dies and is gone forever.

Kybella is indicated for application to the submental region of the neck. The submental area is also known physically as the submental triangle (or suprahyoid triangle). In addition to fat, there are muscles and ligaments in the deep region of the submental area. Kybella is not indicated for injection into any muscle or fat deep to the neck muscles. Kybella is only FDA approved and indicated to treat the fat in the submental region, deep to the skin but above the neck muscles that also are located in the submental triangle. Some people have an abundance of fat beneath the platysma muscle in the submental area. The fat below the platysma muscle is not indicated to be injected with Kybella. If this fat is injected either inadvertently or purposely, there are reports of patients experiencing dysphasia (difficulty swallowing). This adverse effect should be temporary but nonetheless is potentially dangerous and concerning to the patient.

When adverse reactions to a medication or procedure occur, the severity occurs on a continuum from mild reactions to more severe episodes. In order to better understand the risks involved using Kybella, let's call more severe adverse reactions of the Kybella procedure as complications. Two temporary potential complications that may occur following Kybella injection are nerve injury and swallowing difficulties. The marginal mandibular nerve is a motor nerve that courses near the submental area. The submental area of the neck is the region where Kybella is injected. If the marginal mandibular nerve is affected by Kybella, some degree of loss of normal movement of the lower lip will be observed. This will typically affect only one side of the lower lip as there are both a left and a right marginal mandibular nerve supplying movement to their respective sides of the lower lip. It would be much more common to have a partial and temporary paresis (muscular weakness or partial paralysis) of the lower lip than a complete paralysis. No cases of complete lower lip paralysis have been reported from the use of Kybella. In order to provide the patient with the safest injection procedure, it is critical that the injecting physician be intimately familiar with the anatomy of the neck and marginal mandibular nerve branch of the facial nerve in particular. During clinical trials of Kybella cases of transient paresis of the marginal mandibular nerve were observed. The median duration of paresis was 44 days (range 1-298 days). All cases of marginal mandibular nerve paresis resolved spontaneously without permanent muscle weakness. Another possible adverse occurrence following the injection of Kybella is dysphasia (difficulty swallowing). Patients who have pre-existing dysphagia (trouble swallowing) should avoid Kybella use as using Kybella may exacerbate the condition. The cause of difficulty swallowing following Kybella injection is not well understood but is likely due to the swelling from the Kybella reaction itself or if the Kybella is injected into the muscle or on the muscle, muscular inflammation ensues and difficulty swallowing will occur. If either lip weakness or difficulty swallowing occur, the patient should expect a full recovery.

The Kybella procedure is performed in an office based setting. The patient will have pre-procedure photographs taken. The patients neck will be cleaned and marked in a sitting position. Topical anesthetic cream will be applied to the treatment area and left in place for approximately 15 minutes. Cold compresses may be used prior to the procedure, during and after the procedure for additional comfort. Also, prior to Kybella injection, a small volume of local anesthetic (Lidocaine) will be injected using a small 30 gauge, 1/2 inch needle into the treatment area. It has been found that this extra step significantly reduces the discomfort of the Kybella treatment. The treatment is actually quite tolerable. It should not be particularly painful when proper time and care is used for the procedure using the above stated technique.