What does Kythera do? How injections reduce double chin and what to expect regarding frequency and swelling

Kythera is a treatment that injects deoxycholic acid into the fat beneath the chin, destroys fat cells, and gradually reduces double chin[1]. In trials of an approved drug with the same ingredient (ATX-101), 66.5% of people met the improvement criterion 12 weeks after the final injection, exceeding placebo at 22.2%[1]. However, this is a result from a different product with the same ingredient, not from Kythera itself.

How does fat decrease after injection?

Fat does not decrease immediately after injection, but gradually. When deoxycholic acid destroys fat cells, the body's cleaning cells remove the fragments, and collagen is then formed[1].

Deoxycholic acid is originally one of the components of bile that dissolves fat and facilitates absorption in the body[2]. As a medication, it is delivered into targeted fat.

How many treatments are needed?

In trials, injections were administered approximately every 28 days, up to a maximum of 6 times[1]. The amount injected decreased with each session, and the reduction in fat was reflected in the figures[3].

Regarding how long results last, findings show that many people maintained results for up to 3 years[2]. However, if body weight increases, remaining fat cells may enlarge.

How much swelling and pain should be expected?

Swelling, pain, and bruising occur frequently, but most are mild to moderate and temporary[4]Numbness and hardening at the injection site may also occur.[2].

Research showed that approximately 1 in 10 people discontinued treatment due to side effects.[2]Pain can be managed with pain relievers before treatment, local anesthesia, and cooling.[4].

What rare side effects should you know about?

Rare reports include skin erosion, ulceration, infection, and temporary paralysis of nerves controlling mouth movement.[5].

A method has been reported in which injection zones are predetermined to ensure medication does not reach near nerves.[6]It is advisable to confirm in advance the extent of the injection area.

What types of double chin does it suit?

It is most suitable for people with moderate to abundant fat under the chin whose appearance concerns them. Clinical trials also targeted such individuals.[3].

After reducing fat, the jawline shape can also be refined with hyaluronic acid.[7]Note that all trials presented here were supported by companies.[2].

What should be confirmed during examination to see if it is right for you?

What you want to confirm is whether the cause of the double chin is fat, or skin laxity and bone structure. If fat is not the primary cause, the changes achievable with injection will be limited.

During examination, ask about the expected number of treatments, how long swelling will be noticeable, and the injection area. If you have plans to meet people, discuss the timing accordingly.