A lip flip is a cosmetic procedure that uses a small amount of Botox (typically 4 to 6 units) to relax the muscle along your upper lip, causing the lip to gently roll outward and appear fuller. Unlike lip filler, it doesn’t add any volume. The result is subtle, creating more of a “pout” by revealing more of the pink part of your upper lip that normally tucks inward when you smile or talk.
How a Lip Flip Works
Your upper lip is controlled by a circular muscle called the orbicularis oris, which contracts every time you speak, smile, or purse your lips. When Botox is injected into the upper border of this muscle, it weakens the muscle fibers just enough that the lip can no longer curl inward as tightly. The result is a soft eversion, where the lip relaxes outward instead of pulling in.
This is why the effect is so different from filler. Filler physically adds material inside the lip tissue to increase its surface area and shape. A lip flip changes nothing about the lip itself. It simply changes how the muscle holds the lip in place, letting more of your natural lip show. The difference is projection versus volume: a lip flip gives you a poutier resting position, while filler gives you a measurably bigger lip.
What the Procedure Feels Like
The appointment itself is fast, often under 10 minutes. A provider injects small amounts of Botox into a few precise points along the upper lip border. Most people describe a brief pinch with each injection. There’s no significant downtime. You can return to your normal routine right away, though you’ll typically be advised to avoid intense exercise or lying face-down for a few hours.
Results aren’t instant. It takes about one week for the Botox to fully relax the muscle, and that’s when your lip will start looking noticeably fuller. If you’re getting a lip flip for a specific event, plan at least 10 days ahead.
How Long Results Last
A lip flip typically lasts between two and five months, which is shorter than most Botox treatments in other areas of the face. The muscle around your mouth is one of the most active in your body, so the Botox wears off faster there. Most people need repeat treatments every two to five months to maintain the look. Over time, some people find their results last slightly longer as the muscle adapts to being relaxed.
Lip Flip vs. Lip Filler
The choice between a lip flip and filler comes down to what you’re trying to achieve. A lip flip is best if your upper lip tends to disappear when you smile, if you want a subtle enhancement, or if you’re curious about a fuller look but not ready to commit to filler. It’s also a good option if you show a lot of gum tissue when you smile, since the relaxed muscle allows the upper lip to rest lower over your teeth.
Filler is the better choice if you want visible volume, more defined lip borders, or control over the exact shape. With filler, you and your provider can add material gradually until you reach the look you want. The results also last significantly longer, generally six months to a year or more depending on the product used.
A lip flip costs considerably less than filler because it uses so few units of Botox. Many people try a lip flip first as a low-commitment way to test whether they like the appearance of a fuller upper lip before investing in filler.
Temporary Side Effects to Expect
Because the muscle controlling your upper lip is partially relaxed, you may notice some quirky functional changes in the first week or two. Difficulty drinking through a straw is one of the most common complaints. Your lip may not seal around the straw as tightly, letting air escape. Some people also notice mild trouble with certain speech sounds, particularly “p” and “b” sounds, which rely on firm lip closure. Whistling can feel off, too.
These effects are normal and short-lived. They reflect your lip adjusting to slightly less muscle control, and they typically resolve within the first couple of weeks as you adapt. If 4 to 6 units were used (the standard dose), the degree of muscle relaxation is mild enough that most people function normally. Problems tend to arise only when too many units are used, which over-relaxes the muscle and makes everyday lip movements genuinely difficult.
Who Gets the Best Results
The best candidates are people whose upper lip curls inward or thins out significantly when they smile. If you’ve noticed that your upper lip looks fine at rest but seems to vanish in photos, a lip flip directly addresses that. It’s also well suited for people who want a natural look and are wary of the “overfilled” appearance that poorly done filler can create.
It’s less effective if your upper lip is already very thin at rest. Because the procedure doesn’t add volume, there’s a limit to how much visible change it can produce if there isn’t much lip tissue to reveal. In that case, filler (alone or combined with a lip flip) tends to deliver more noticeable results.