Lip Flip vs Lip Filler
Filler adds material to your lip. A lip flip does not. A lip flip is a few units of botulinum toxin that relax the muscle around your mouth, so the upper lip rolls out slightly and a little more pink shows. Nothing is added, and your lip is not any bigger.
What is injected
Usually 4 to 6 units, placed in the orbicularis oris — the ring of muscle around the mouth. Dysport and Xeomin can be used the same way.
A gel made of a sugar your body already makes. It takes up space, so the lip is physically larger. Half a syringe to a full syringe is a common amount.
What it changes
The upper lip turns outward a little, so more of the pink border shows. Most visible when you smile or talk.
Real added volume. It can also change the outline of the lip and the balance between top and bottom.
How big the change is
The only study to measure it with 3D imaging found a gain of 0.43 mm. That is a real change in how the lip sits, and it is smaller than most people picture.
There is no fixed figure — it depends on how much gel goes in and where. That is the real difference: filler scales with the dose, a lip flip does not.
How fast you see it
Nothing happens on the day. It builds over the first week and peaks around two weeks.
You leave with fuller lips. They will also be swollen for two to five days, so they look bigger at first than the settled result.
How long it lasts
Peaks at about two weeks. Measured objectively, it was already heading back toward baseline at 30 days and had essentially returned by 90. Most people book a repeat every two to three months.
In the trial the FDA approved Juvederm Ultra XC on, 79 in 100 people had a visible improvement in lip fullness at three months. At twelve months that had fallen to 56 in 100. So "lasts a year" is true for a bit over half of people, not all of them.
What it costs
There is no published national average for a lip flip on its own. At 4 to 6 units it is usually the smallest and cheapest item on an injector's list.
That is the American Society of Plastic Surgeons average, for one syringe. It does not include the follow-up appointment.
What can go wrong
Trouble whistling, drinking through a straw, or making "p" and "b" sounds. In the one study that tracked this, every participant had at least one mild effect — numbness was the most common — and all cleared on their own.
Swelling and bruising are normal for several days. Lumps can be smoothed or dissolved. The serious one is the gel blocking a small blood vessel. This happens in under 1 in 100 filler procedures. Lips are one of the areas where it happens.
If you do not like it
Botulinum toxin cannot be reversed. But it wears off within weeks, which is the point in its favour.
An enzyme called hyaluronidase breaks hyaluronic acid down, usually within a day or two. This is also the emergency treatment if a vessel is blocked.
Who tends to be happy with it
The number almost no comparison gives you
Search this question and you will find dozens of pages saying a lip flip lasts about eight weeks. Very few say how much it actually moves your lip, because until recently nobody had measured it.
In 2026, a study in Aesthetic Plastic Surgery did. Seventeen women received 4 units of onabotulinumtoxinA, 2 per side, and their lips were measured with 3D stereophotogrammetry rather than by eye. Upper lip height rose from 8.31 mm to 8.74 mm at day 15. By day 30 it was already falling back, and by day 90 it was essentially where it started.
Two things follow from that. The effect is small — under half a millimetre, and the authors were clear it comes from the muscle relaxing rather than from any added volume. And the common eight-to-twelve-week figure looks generous: measured objectively, most of the change was gone within a month.
That does not make a lip flip a bad choice. It makes it a different choice. It is a low-cost, low-commitment adjustment to how your lip sits, and it is fair to judge it on that.
Filler has the same problem in reverse. It is widely described as lasting a year, and the FDA's own approval document for Juvederm Ultra XC shows why that needs a qualifier: 79 in 100 people had a visible improvement at three months, but only 56 in 100 still did at twelve. A year is the outer edge of the range for a lot of people, not the middle of it.
Worth asking before you book
- How many units are you using, and where? Four to six is the range the published reports use.
- Who will be injecting me, and what are they trained as? Injectors range from physicians to nurses depending on the state.
- What do you do if it is uneven at two weeks?
- For filler: which product, how much, and do you keep hyaluronidase on site?
That last one matters more than it sounds. Hyaluronidase is both the fix for a lumpy result and the emergency treatment if a vessel is blocked, and it works best in the first few hours.
Get help the same day if
- The pain after filler is severe, or gets worse instead of better
- The lip or the skin around it turns white, blotchy, or dusky purple
- The area goes cold, or the colour does not come back when you press and release
- You develop blisters, or any change in your vision
These are the signs of a blocked blood vessel. It is uncommon, but it is time-sensitive — contact the injector who treated you immediately, and go to an emergency department if you cannot reach them.