Comparison

Kybella vs Morpheus8

Kybella is an FDA-approved drug for fat under the chin. Morpheus8 is a cleared device that works on skin and, in the one study that measured it, left the fat layer unchanged.
Written & medically reviewed by the Dermapedia team
At a Glance

Kybella dissolves fat. Morpheus8 works on skin. Kybella is deoxycholic acid, a bile acid injected into the fat pad under the chin, where it breaks open fat cells. Morpheus8 is radiofrequency microneedling - needles that place heat inside the dermis so collagen remodels.

The regulatory contrast is genuinely useful, and it runs the opposite way to most people's expectation. Kybella is a drug, approved under NDA 206333 on 29 April 2015 for "improvement in the appearance of moderate to severe convexity or fullness associated with submental fat in adults." A drug approval requires adequate and well-controlled trials showing the product works for that specific use. Morpheus8 is a device, cleared through 510(k), a route that mainly requires showing the device is much like one already on the market - and its clearances name no cosmetic use at all: electrocoagulation and hemostasis, surgical wording for sealing tissue and stopping bleeding (K192695, 2019), then coagulation or contraction of soft tissue (K231790, 2023).

So the treatment that cleared the higher bar is approved for exactly the thing the other one is informally sold for. Double chins.

And Morpheus8 does not reduce fat. The one study that measured it took ultrasound scans under the chin in a split-face trial with 30 people completing, and found the dermis thickened while the fat layer did not change significantly. The paper is titled "...without Lipolysis."

Kybella
Allergan/AbbVie, injectable deoxycholic acid, a drug
Morpheus8
InMode, radiofrequency microneedling, a device

What it is

A drug that breaks open fat cells - deoxycholic acid - injected into the fat under the chin

Approved under NDA 206333 on 29 April 2015. There is no device clearance and no 510(k), because it is not a device.

An array of insulated microneedles delivering radiofrequency heat inside the skin

Cleared through 510(k) under product code GEI, the FDA's category for electrosurgical cutting and coagulation devices.

How it works

Chemistry. A bile acid that normally emulsifies dietary fat, injected into the fat pad, breaks open the fat cell membranes

The debris is then cleared by the immune system. The drug is not selective for fat cells, which is why injection technique and anatomy matter so much - misplaced, it will damage skin, muscle or nerve.

Heat. Needles place fractional columns of thermal injury in the dermis, which contracts and rebuilds collagen over months

What it is best at

The fat pad under the chin, and nowhere else

The label's Limitations of Use say the safe and effective use of Kybella for fat outside the submental region "has not been established and is not recommended."

Skin - texture, acne scarring and mild laxity

The best-evidenced use of this device class is atrophic acne scars. There is no dedicated trial of radiofrequency microneedling for submental fat.

What it is cleared to treat

Approved, not cleared, for "improvement in the appearance of moderate to severe convexity or fullness associated with submental fat in adults"

That is the whole approved indication, word for word.

Electrocoagulation and hemostasis (K192695, 2019), then coagulation or contraction of soft tissue (K231790, 2023)

No Morpheus8 clearance names wrinkles, laxity, acne scars, a double chin or any cosmetic use. Above 62 millijoules per pin, the clearance limits use to skin types I to IV.

Both
These are two different standards of proof at the same agency. A drug approval means trials showed the product works for the stated use. A 510(k) clearance means the device was judged much like an earlier one - it is not a finding that a benefit was demonstrated. Treating with a device outside its cleared wording is legal and routine, and most aesthetic device use is exactly that.

Downtime

Substantial, and worth planning around. Marked swelling, bruising, pain, numbness and firmness under the chin after each session

The conventional description is roughly one to two weeks, though that duration is not a figure taken from the label. Of the two, this is the one with visible, socially awkward recovery.

Redness in essentially everyone, swelling in about a third, and roughly three to four days of visible recovery

Barrier function, measured as water loss through the skin, peaks on days one to three and is back to baseline by day seven.

Comfort

A grid of injections into the fat under the chin, repeated at each session

The labelled risks that matter are injury to the marginal mandibular nerve, which causes an uneven smile, and difficulty swallowing.

Needling plus heat; topical numbing is standard

No study has measured pain for facial radiofrequency microneedling against Kybella, so no comparison is offered. The one published pain figure in this literature comes from a very different setting - abdominal stretch marks with non-insulated needles, where radiofrequency microneedling scored 5.35 out of 10 against 2.35 for fractional CO2 - and it should not be read across to a facial treatment.

Sessions

Typically up to 6 sessions, at least a month apart
Manufacturer labelling says 1 to 6 treatments every 3 to 6 weeks, and generally 3 to 5 at mild-to-moderate depth settings

Who tends to be happy with it

Best for
Someone with a distinct pad of fat under the chin who wants that fat gone and can absorb visible swelling after each session.
The mindset
Fat is the problem. Trade downtime for it.
Best for
Someone whose complaint is the skin: texture, acne scarring, crepiness, mild slackness, under the chin or elsewhere.
The mindset
Skin quality, built slowly over months.

The swelling after Kybella is the part people underestimate

Most treatments on this site have little or no visible recovery. Kybella is the exception. Marked swelling, bruising, pain, numbness and firmness under the chin follow each session, and people generally plan around them. The conventional description is roughly one to two weeks; that is clinical convention rather than a figure quoted from the label.

Two labelled risks are worth knowing before you consent. The first is injury to the marginal mandibular nerve, which causes an uneven smile. The second is difficulty swallowing. There is no boxed warning on the label. The drug is not selective for fat cells, so where it goes matters - which is the argument for having it injected by someone who does it often and maps the anatomy first.

Morpheus8 does not remove fat, and the fat story runs the other way

There is no dedicated trial of radiofrequency microneedling for submental fat. The one study that measured the fat layer found it unchanged while the dermis thickened.

What does appear in the record is unwanted fat loss. Fat loss is the third most-reported complication category in the FDA's post-market database for radiofrequency microneedling: 26 of 224 reported events between January 2013 and October 2025. MAUDE is a voluntary reporting system with no denominator, so that is a proportion of reports and not a chance that it happens to a patient. No incidence rate has been published, no case series describes it, and there is no established treatment for it.

The awkward part is that the mechanism marketing invokes to sell Morpheus8 for a double chin is the same one that shows up in the complaint data.

Almost none of the radiofrequency microneedling evidence was generated on Morpheus8

A PubMed search for Morpheus8 returns 16 records, and no randomised controlled trial was found. The research behind this device class comes from other machines - Lutronic Genius and Infini, Jeisys, Pollogen, Lumenis and several unnamed devices. The class evidence is real; it is simply not this brand's evidence.

What "lasting" means for each

Kybella destroys fat cells directly, and the label's expectation is a course of up to six sessions rather than a single fix. There is no published durability figure for it, so none is quoted.

For radiofrequency microneedling, the longest properly measured follow-up in the literature is six months. The clinic claim of one to three years has no published source. Collagen remodelling is measurable on biopsy by around four months, clinically meaningful change is generally not significant at one month, is significant at three, and holds at six. Beyond that there is no controlled data - and ageing carries on regardless of what either treatment did.

Before you book

If you get cold sores, tell your provider when you book, not on the day. Antiviral medicine is started in advance, so it has to be prescribed beforehand. There is no published data on cold sore reactivation after radiofrequency microneedling specifically; the practice is carried over from laser resurfacing, where reactivation is well documented and prophylaxis is standard.

Before radiofrequency treatment, also disclose a pacemaker or an implantable defibrillator, and any metal implant near the treatment area. These are labelled contraindications for radiofrequency devices generally, and they are precautionary rather than tested - the right people to advise you are your cardiology team.

Get emergency help now

  • Difficulty swallowing, or any difficulty breathing, after a Kybella session - difficulty swallowing is a labelled risk of the drug and needs urgent assessment
  • Fever or chills after either treatment
  • Redness around a treated area that is visibly spreading hour by hour, or pus coming from the skin - these are signs of a spreading infection

Call your provider if

  • Your smile becomes uneven, or one side of your mouth does not move properly, after Kybella
  • Swallowing feels different or uncomfortable after a session
  • Swelling, pain or redness is increasing after day three instead of settling
  • Skin blisters or crusts, or an open area appears
  • A grid pattern of marks is still visible beyond about a week after Morpheus8
  • The treated skin darkens noticeably over the following weeks
  • An area starts to look hollow or dented compared with the other side
  • A cluster of small painful blisters appears - this can be a cold sore flare

Related

Questions people ask+
Which one gets rid of a double chin?Kybella, if the double chin is mostly fat. That is its approved indication and the only place it is meant to be used. Morpheus8 has no evidence for reducing submental fat, and the one study that measured the fat layer found it unchanged.
Then what is Morpheus8 doing under the chin?Working on the skin. There is evidence in this device class for tightening submental skin, not for removing the fat beneath it. Some people's "double chin" is largely loose skin, and those are the people this suits.
Why does it matter that Kybella is a drug and Morpheus8 is a device?Because the standards differ. A drug approval requires trials showing the product works for the stated use. A 510(k) device clearance mainly requires showing the device is much like one already sold. Same agency, very different bar - and it is worth knowing which one is behind a claim.
How bad is the swelling after Kybella?Real, and visible. Marked swelling, bruising, pain, numbness and firmness under the chin follow each session. The conventional description is roughly one to two weeks, though that duration is not a figure quoted from the label. Most people plan their diary around it.
How many Kybella sessions will I need?Typically up to six, at least a month apart, depending on how much fat is there.
Can Kybella be used on jowls, bra fat or inner thighs?Not on-label. The label's Limitations of Use say the safe and effective use of Kybella outside the submental region "has not been established and is not recommended."
Can I have both?They do different jobs, and it is common enough to have both fat and loose skin. No published study has tested the two together, so sequencing is a clinical judgement - and it is worth remembering that removing fat can make loose skin more obvious.