Fat-dissolving injections: what they do, what they cost and what to ask before you book
Injections that dissolve a double chin sound like an easy fix. The real question is whether a small, localised fat pocket is the problem at all, or whether loose skin and jawline definition are doing most of the work.
In The Ageless Blueprint, Dr Leah rates fat-dissolving injections out of 10, names the product Dr Leah prefers and why, and explains when Dr Leah would assess a patient for a more involved procedure instead. This page covers what the injections involve.What fat-dissolving injections are
Fat-dissolving injections are solutions injected into a small pocket of fat, most often under the chin or along the jawline, that damage fat cells so the body gradually clears the treated tissue. In the UK the products include Aqualyx, Deso and Belkyra, a deoxycholic acid product sold in the United States as Kybella. The products are not identical in formulation or in how they behave.
They are for small, localised fat reduction, never for weight loss. The injections reduce fat but do nothing for loose skin, and in some patients the skin looks looser once the fat beneath it has gone, so a separate tightening treatment may follow. For substantial laxity across the neck, lower face and jawline, or for a much sharper jawline, clinics may suggest a more involved procedure combining radiofrequency beneath the skin with aspiration liposuction, which carries a longer recovery.
Generally used for
- A small fat pocket under the chin in someone with relatively firm skin
- Softening a fuller jawline where fat rather than skin is the cause
- Patients who want to avoid a surgical or liposuction procedure
What the guide covers that this page does not
- Dr Leah’s rating out of 10, and the reasons behind it
- The product Dr Leah prefers among Aqualyx, Deso and Belkyra, and why
- What Dr Leah combines the injections with to tighten the skin afterwards
- When Dr Leah assesses a patient for QuantumRF or NeckTite with liposuction instead
What to expect
| Results | Gradual, developing over weeks as the body clears the treated fat, and often subtle. Two or three sessions are commonly needed to judge the outcome. |
|---|---|
| How long it lasts | Fat cells that are destroyed do not return, so the reduction is long-lasting provided weight is stable. Remaining fat cells can still enlarge with weight gain. |
| Appointment and downtime | A short injection appointment. Swelling is the main feature of recovery and can be marked for approximately a week; tenderness and bruising are also likely. Plan around social and work commitments. |
| What can go wrong | Temporary numbness and firmness in the treated area. Uncommon complications under the chin include an uneven smile from nerve irritation and difficulty swallowing. Loose skin may become more noticeable once the fat is reduced. |
| Cost | Typically £250 to £550 per session in UK clinics, with two to three sessions usually recommended, so the course total is the figure to compare. |
Five things to ask before you book
- Exactly which product are you using, and why that one rather than the others?
- Is my double chin mainly fat, mainly loose skin, or both? Will I need a tightening treatment afterwards?
- How much swelling should I expect, and for how many days should I clear my diary?
- What is your plan if I get an uneven smile or difficulty swallowing after treatment?
- At what point would you tell me that injections are the wrong approach and a procedure would serve me better?
Dr Leah’s verdict is in the guide
Chapter 8 of The Ageless Blueprint rates fat-dissolving injections out of 10 and explains the reasoning in Dr Leah’s own words. It names the product Dr Leah prefers and what Dr Leah has observed about swelling with each, describes the tightening treatment Dr Leah pairs with the injections in a younger patient with firm skin, and sets out the degree of laxity at which Dr Leah would discuss QuantumRF with aspiration liposuction instead. Three pages, with illustrations.
This page gives general information and does not replace a consultation with a qualified practitioner who can assess your face, skin and medical history. Prices are typical UK ranges, accurate as of September 2026, and vary between clinics. For adults aged 18 and over.
Common questions
They can reduce a small, localised fat pocket under the chin, and the change develops gradually over more than one session. They do not tighten loose skin, so a larger or softer double chin may need something else. Dr Leah’s rating and the alternative Dr Leah assesses for are in chapter 8.
Swelling is the part of recovery patients notice most, and it can be marked for approximately a week. Tenderness, bruising, temporary numbness and firmness are also common.
No. Kybella is the US brand of Belkyra, a deoxycholic acid product. Aqualyx and Deso are different products used in UK clinics. All work by damaging fat cells so the body clears them, but they are not identical, so ask which one a clinic proposes.