Citing what it called "newly identified risks," the FDA is reinforcing its warnings about adverse events associated with injections of deoxycholic acid (Kybella).
In a drug safety communication announcing the update to the deoxycholic acid label, the agency said that adverse events — such as injection site nodules and masses that may or may not have resolved over time — have been identified with approved and unapproved uses. Kybella, manufactured by Allergan Aesthetics (an AbbVie company), was approved in 2015 to improve the appearance of submental fat but is used off label in other areas of the body.
Through a search of the FDA's Adverse Event Monitoring System and the medical literature, the agency said it identified 129 cases of adverse events when deoxycholic acid injection was used outside the chin area, including blurred or reduced vision when injected around the eyes and facial paresis and paresthesia.
The agency said it also found 117 cases of unresolved nodules (3 cm or smaller) or masses (larger than 3 cm) associated with deoxycholic acid injections, which had been present for a mean of about 5 months.
The formation of nodules had been observed in clinical trials, affecting some 13% of patients who participated, according to Kybella's FDA-approved label. But the label has been updated to note that "some nodules and masses may not resolve and medical intervention may be required."
Although the label has always indicated that Kybella should not be used outside the submental area, this is now reiterated in the warnings and precautions section.
The literature contains post-marketing reports of injuries and adverse events associated with deoxycholic acid injections. A 2024 paper in Aesthetic Surgery Journal Open Forum, described what the authors called "avoidable, uncommon, and serious adverse events" that have been reported in real-world settings.
Among those: marginal mandibular nerve injury; hematoma; alopecia at the injection site; vascular injury; skin ulceration and necrosis; abscess; inadvertent intraarterial injection; a case of pyoderma gangrenosum; ulnar nerve palsy; and incorrect injection or accidental use at an unapproved site.
The article's authors wrote that there are "proactive measures" that could be used to prevent adverse events.
During the 2015 FDA advisory committee meeting on Kybella, agency officials indicated concern about marginal mandibular nerve injury, which was experienced by 4% of those receiving the injections, compared to 1% of those getting placebo. Although the injuries spontaneously resolved, some lasted as long as 298 days.
The FDA is now urging clinicians to review Kybella prescribing information before use and to advise patients to seek medical attention if they experience any adverse events, including signs of marginal mandibular nerve paresis, difficulty swallowing, or serious injection site reactions.
AbbVie provided support for medical writing for the Aesthetic Surgery Journal Open Forum paper, and one of the authors serves as an advisory board member, principal investigator, and consultant for AbbVie/Allergan Aesthetics.
Healthcare providers and patients can report adverse events associated with deoxycholic acid injections or other medicines to the FDA MedWatch program.
Alicia Ault is a Saint Petersburg, Florida-based freelance journalist whose work has appeared in many health and science publications, including Smithsonian.com. You can find her on X @aliciaault and on Bluesky @aliciaault.bsky.social.
Facts Only
* The FDA reinforced warnings about adverse events associated with deoxycholic acid injections.
* Adverse events included injection site nodules and masses that may or may not have resolved over time.
* Adverse events were identified in approved and unapproved uses of the drug.
* A search identified 129 cases of adverse events when deoxycholic acid was injected outside the chin area, including blurred vision around the eyes and facial paresis/paresthesia.
* 117 cases of unresolved nodules (3 cm or smaller) or masses (larger than 3 cm) were associated with injections present for a mean of about five months.
* Clinical trials observed nodule formation in 13% of patients who participated in Kybella use.
* The label was updated to state that some nodules and masses may not resolve and medical intervention may be required.
* Post-marketing reports described injuries including marginal mandibular nerve injury, hematoma, alopecia, vascular injury, skin ulceration and necrosis, abscess, inadvertent intraarterial injection, pyoderma gangrenosum, ulnar nerve palsy, and incorrect injection or accidental use at an unapproved site.
* Officials expressed concern about marginal mandibular nerve injury in the 2015 advisory committee meeting, which affected 4% of recipients compared to 1% of placebo recipients.
* The FDA urged clinicians to review prescribing information and advise patients to seek medical attention for adverse events like signs of marginal mandibular nerve paresis or difficulty swallowing.
Executive Summary
Full Take
The narrative shifts from regulatory oversight to real-world morbidity, highlighting a critical disconnect between approved use and observed patient outcomes. The pattern emerging is the gradual emergence of previously latent risks—specifically, delayed and persistent physical changes following cosmetic procedures where long-term tissue reactions are not fully captured in initial approval or short-term trials. The fact that adverse events were found across both approved and off-label uses suggests a systemic gap in risk communication regarding non-target anatomical sites and long-term sequelae. The description of severe, potentially irreversible injuries like nerve damage (marginal mandibular nerve injury) occurring in real-world settings underscores the necessity of proactively identifying "avoidable" risks, as suggested by post-marketing literature. The concern about unresolved nodules compels an examination of follow-up protocols; if 13% developed nodules in trials, the discrepancy between resolution rates and reported persistence demands scrutiny regarding intervention strategies. The repeated emphasis on clinical review and patient reporting signals a recognition that safety monitoring must extend beyond initial trial endpoints to account for cumulative exposure across various application contexts.
Bridge Questions: What systemic changes are required in regulatory frameworks to mandate longitudinal follow-up for cosmetic injections? How can the current mechanisms of post-marketing reporting be enhanced to capture delayed or subtle adverse events, especially those related to nerve and vascular structures? What responsibility exists for ensuring that off-label use carries commensurate risk disclosure based on comprehensive safety data?