What are the guidelines and safety considerations for using deoxycholic acid injections for facial rejuvenation and submental fat reduction?

Deoxycholic Acid Injections for Submental Fat Reduction

Deoxycholic acid injection (KYBELLA®) is FDA-approved exclusively for moderate to severe submental fat reduction in adults and should not be used for facial rejuvenation or fat reduction outside the submental area. 1

FDA-Approved Indication and Limitations

• KYBELLA is indicated only for improvement in the appearance of moderate to severe convexity or fullness associated with submental fat ("double chin") in adults. 1
• The FDA explicitly states that "the safe and effective use of KYBELLA for the treatment of subcutaneous fat outside the submental region has not been established and is not recommended." 1
• This is not a facial rejuvenation treatment—it is specifically a fat reduction agent that causes adipocyte lysis when injected into subcutaneous fat tissue. 2

Dosing Protocol

• Administer 2 mg/cm² injected into subcutaneous fat tissue in the submental area. 1
• A single treatment consists of up to 50 injections of 0.2 mL each (maximum 10 mL total), spaced 1 cm apart. 1
• Up to 6 treatment sessions may be administered at intervals of at least 1 month apart. 1
• Efficacy is typically assessed 12 weeks after the last treatment session. 2

Critical Safety Considerations and Contraindications

Absolute Contraindications

• Do not administer if the patient has an infection in the treatment area. 1

Patient Selection Requirements

• Screen patients for other causes of submental fullness including thyromegaly and cervical lymphadenopathy before treatment. 1
• Exercise extreme caution or avoid treatment in patients with excessive skin laxity or prominent platysmal bands, as fat reduction may result in aesthetically undesirable outcomes. 1
• Use caution in patients with prior surgical or aesthetic treatment of the submental area, as altered anatomy or scar tissue may impact safe administration. 1

Anatomical Injection Restrictions to Prevent Nerve Injury

The marginal mandibular nerve is at high risk during deoxycholic acid injection—injury presents as asymmetric smile due to lip depressor muscle paresis. 1

To avoid marginal mandibular nerve injury:

• Never inject above the inferior border of the mandible. 1
• Never inject within 1-1.5 cm below the inferior border of the mandible (from the angle of the mandible to the mentum). 1
• Inject only within the target submental fat treatment area between the dermis and platysma (pre-platysmal fat). 1
• Avoid injection into the platysma muscle itself. 1

Serious Adverse Events

Inadvertent intra-arterial injection can cause tissue necrosis—this is a medical emergency requiring immediate intervention. 3

Other serious complications include:

• Nerve injury causing facial muscle weakness or uneven smile 1
• Dysphagia (trouble swallowing) 1
• Hematoma or bruising at injection sites 1
• Tissue necrosis around the injection site 1
• Hair loss, open sores (ulcers), or infection at the treatment area 1

Common Side Effects

• Swelling, redness, pain, areas of hardness, and numbness in the treatment area are the most common side effects and typically resolve within approximately one treatment interval. 1, 2

Special Populations and Drug Interactions

• Inform patients taking antiplatelet or anticoagulant medications of increased bleeding risk. 1
• Safety in pregnancy and breastfeeding is unknown—discuss risks versus benefits. 1
• Not approved for use in children under 18 years of age. 1

Off-Label Use: Not Recommended for Facial Rejuvenation

While some case reports describe off-label use for facial contouring, brassiere line fat, and other non-submental areas with similar safety profiles 4, 5, these applications lack FDA approval and established safety data. The evidence provided focuses on platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) for facial rejuvenation 6, which are entirely different modalities from deoxycholic acid and should not be confused with fat reduction injections.

Clinical Pitfall to Avoid

Do not confuse deoxycholic acid (a fat-dissolving agent) with regenerative treatments like PRP/PRF or dermal fillers used for facial rejuvenation. 7 Deoxycholic acid destroys adipocytes and is inappropriate for skin quality improvement, wrinkle reduction, or volumization—it is exclusively for fat reduction in the submental area. Using it off-label for "facial rejuvenation" risks serious complications including nerve injury, tissue necrosis, and aesthetically poor outcomes. 1, 3