Thin, uneven or less defined lips? How lip filler (丰唇, 唇部填充) works, why it can look completely natural, what to expect afterwards, and what to do if filler from elsewhere has gone wrong
Medically reviewed by Dr. Adriene Chee, Medical Director, Verve Clinic. Last updated: October 2026.
Maybe your lips have always been thin, and lipstick never looks quite right. Maybe one side is fuller than the other. Maybe your lips have lost their shape and fullness over the years. Or maybe you would love a little more definition, but the thought of “duck lips” puts you off completely.
You are not alone, and that last worry is the one we hear most. The good news is that well-planned lip filler does not have to look done. In this guide, Dr. Adriene Chee, a doctor with more than 10 years of experience, explains how lip filler works, what it can and cannot do, and how we keep results natural.
What is lip filler?
In short: Lip filler (玻尿酸丰唇) is a hyaluronic acid gel injected into the lips to add volume, improve shape and define the lip border. Most patients need one session of 0.5 to 1 ml. Results are visible straight away, settle fully in about 2 weeks and last around 6 to 9 months. If needed, the filler can be dissolved.
Hyaluronic acid is a substance your body already makes. It holds water, which is why it keeps skin plump and hydrated. As a dermal filler, it is shaped into a smooth gel that a doctor places precisely, a little at a time, to build the shape you want. Lip filler is also known in Malay as filler bibir.
Hyaluronic acid filler is one of the most popular non-surgical treatments in the world: according to the ISAPS 2024 global survey, HA filler procedures rose by 5.2% to 6.3 million.
What can lip filler fix?
Lip filler can add volume to thin lips, balance uneven lips, define the lip border and restore lips that have thinned with age. It is not only about making lips bigger: most of our patients come for balance, shape and definition.
| Concern | What lip filler does |
|---|---|
| Thin or flat lips | Adds gentle volume so lips look fuller and softer |
| Uneven lips | Balances the left and right sides, or the upper and lower lip |
| Undefined lip border | Sharpens the lip line and Cupid’s bow so lips look more defined |
| Ageing lips | Restores lost volume, softens fine lip lines and lifts downturned corners |
| Dry, dull lips | Hydrates from within, so lips look smoother and healthier |
Will lip filler look natural?
Yes, when it is planned around your face rather than a trend. Natural results come down to three things: the right amount, the right placement and the right proportions.
Proportion matters more than size. In a 2017 study in JAMA Facial Plastic Surgery with over 500 participants, the most attractive lips had a lower lip about twice the size of the upper lip, a 1:2 ratio. Lips with the opposite proportion, an upper lip twice the size of the lower lip, were rated least attractive. That is why we look at your whole face, not just your lips, before we start.
| Natural lip filler | Overdone lip filler | |
|---|---|---|
| Amount | 0.5 to 1 ml, matched to your face | Too much at once, or repeated top-ups before it settles |
| Shape | Follows your own lip shape | Rounded “sausage” or “duck” shape |
| Lip border | Crisp and soft | Filler spreads above the lip line |
| Proportion | Lower lip slightly fuller than upper lip | Upper lip as large as, or larger than, the lower lip |
| Movement | Lips move normally when you talk and smile | Stiff or bulky when you smile |
What happens during a lip filler treatment?
Lip filler takes about 30 to 45 minutes, including numbing. Your doctor assesses your lips, numbs them, then injects small amounts of filler with a fine needle, checking the shape with you before you leave.
- Consultation and lip assessment. Your doctor looks at your lip shape, proportions and symmetry, listens to what you want, and explains what will suit you.
- Numbing cream. We apply numbing cream to keep you comfortable.
- Precise injection with a fine needle. Small amounts of filler are placed where they are needed, for shape, border and volume.
- Check together. We check the shape and symmetry with you in the mirror before you leave.
- Aftercare advice. You go home with simple aftercare instructions, and can usually return to work the same day or the next day.
| Quick facts | |
|---|---|
| Amount | Usually 0.5 to 1 ml |
| Sessions | One session for most patients |
| Technique | Fine needle, for precise shape and definition |
| Treatment time | About 30 to 45 minutes, including numbing |
| Comfort | Numbing cream; most patients feel pressure and a few pinches |
| Downtime | Minimal; mild swelling for a few days |
| Final result | At around 2 weeks |
| Lasts | About 6 to 9 months |
| Reversible | Yes, with hyaluronidase |
Lip filler swelling and recovery: what to expect
Swelling is normal and temporary. Your lips will look fuller than the final result for the first few days, so try not to judge the shape too early.
| When | What you may notice |
|---|---|
| Straight after | Lips look fuller and more defined; mild swelling and tenderness |
| Days 1 to 3 | Swelling is usually at its most noticeable; small bruises are possible |
| By about 1 week | Most swelling has gone down and lips feel softer |
| Around 2 weeks | The filler has settled and you see your final result |
Aftercare tips for the first 24 to 48 hours:
- avoid pressing, massaging or squeezing your lips
- avoid strenuous exercise, saunas and alcohol
- use a cold compress gently if you feel swollen
- keep your lips clean and avoid lipstick for the first day
How long does lip filler last?
Lip filler usually lasts about 6 to 9 months. Because your lips move all day when you talk, eat and smile, filler breaks down faster there than in the chin, nose or cheeks.
Research supports this. A 2021 meta-analysis in Frontiers in Surgery of hyaluronic acid lip filler found that 91% of patients still had visibly fuller lips at 2 months and 74% at 6 months, falling to 46% at 12 months. Many patients choose a small maintenance treatment when they feel their lips have softened.
Lip filler before and after
This is a real patient treated at Verve Clinic. Results vary from person to person.
Can bad lip filler be fixed or dissolved?
Yes. Hyaluronic acid filler can be dissolved with an enzyme called hyaluronidase. After about 1 week, once the lips have settled, your doctor can reassess and refill gently if you wish.
We see many patients whose lips were treated elsewhere and who are not happy with the result. Common reasons include lips that look overfilled, lumps you can feel, uneven sides, or filler that has moved above the lip line, sometimes called a “filler moustache”.
Here is how we usually correct it:
- Assess. Your doctor examines your lips to understand what has happened and where the filler sits.
- Dissolve. We dissolve the unwanted filler with hyaluronidase, an enzyme that breaks down hyaluronic acid.
- Wait about 1 week. This lets the swelling settle and shows us your natural lips again.
- Reassess and refill, only if you want to. If you would like, we rebuild your lips gently, with a natural amount and shape.
Is lip filler safe?
When performed by a doctor, lip filler is a well-established treatment, and most side effects are mild and temporary. The 2021 meta-analysis found that the most common effects were tenderness, swelling and bruising, which settled on their own within days to a few weeks.
Your safety comes first at every step. Treatment is performed by a doctor who understands the anatomy of the lips, and we always keep hyaluronidase in the clinic. Lip filler is postponed during pregnancy and breastfeeding, and if you have an active cold sore or infection. If you get cold sores often, let your doctor know beforehand.
What does the research say?
Hyaluronic acid is the most studied filler for lips. Alongside the 2021 meta-analysis of nearly 1,500 participants, a 2022 multicentre study in Aesthetic Surgery Journal Open Forum followed 60 patients after lip filler. At 30 days, 93.2% had visibly fuller lips, and patients’ satisfaction with their lips improved markedly. No serious side effects were reported.
Who is a good candidate for lip filler?
You may be a good candidate if you:
- have thin, uneven or less defined lips that bother you
- have noticed your lips thinning or losing shape with age
- want results that look natural, not obviously “done”
- had filler elsewhere and want it corrected
- are not pregnant or breastfeeding
If you are deciding between filler and other injectables for different areas of the face, our guide Dermal Fillers vs Collagen Biostimulators explains how they compare.
A note from Dr. Adriene Chee: “The biggest fear I hear is, I don’t want to look fake. I understand that completely. For me, beautiful lips are lips that suit your face. We use the amount you need, place it precisely, and the best compliment is when people say you look well, without knowing why.”
Frequently asked questions
How much lip filler do I need?
Most patients need 0.5 to 1 ml in a single session. Your doctor decides the amount based on your lip shape, your face and the result you want. We prefer to start conservatively, because it is easy to add a little more later but better not to overdo it.
How long does lip filler last?
Lip filler usually lasts about 6 to 9 months. Lips move constantly when you talk, eat and smile, so filler breaks down faster there than in areas such as the chin or cheeks.
Will my lip filler look natural?
Yes, when the amount and placement suit your face. Our aim is your lips, but better: more balanced, better defined and hydrated, not obviously “done”. Overdone lips usually come from too much filler, or filler built up over many sessions without allowing it to settle.
Does lip filler hurt?
Most patients find it very manageable. We apply numbing cream before treatment and use a fine needle. You may feel some pressure and a few pinches, and the lips can feel tender for a day or two afterwards.
How long does the swelling last?
Swelling is normal and usually most noticeable in the first 1 to 3 days. Most of it settles within about a week, and your lips reach their final shape at around 2 weeks.
Can I go back to work after lip filler?
Yes. Most patients return to work the same day or the next day. If you have an important event, plan your treatment at least 2 weeks ahead so any swelling or bruising has settled.
Is lip filler permanent?
No. Hyaluronic acid is broken down naturally by the body over about 6 to 9 months in the lips. It can also be dissolved earlier with hyaluronidase if needed.
What happens when lip filler wears off?
Your lips gradually return to their previous shape. There is no sudden change, and many patients choose a small maintenance treatment when they feel the result softening.
Can lip filler be dissolved?
Yes. Hyaluronic acid filler can be dissolved with an enzyme called hyaluronidase. This is one reason hyaluronic acid filler is the preferred choice for lips: if you are not happy, it is not permanent. We always keep hyaluronidase in the clinic.
I had lip filler elsewhere and I am not happy. Can you help?
Yes. If your lips feel overfilled, lumpy or uneven, or the filler has moved above the lip line, we can dissolve it with hyaluronidase. We then wait about 1 week for the lips to settle, reassess, and refill gently only if you want to.
Can lip filler fix uneven lips?
Yes, in most cases. Small amounts of filler placed precisely can balance the left and right sides, or the upper and lower lip, so your lips look more even at rest and when you smile.
Can lip filler help thin lips caused by ageing?
Yes. Lips lose volume and definition with age, and fine lines can form around the mouth. Filler restores some of that lost volume, redefines the lip border and can soften fine lip lines, for a fresher but natural look.
Can I choose the shape of my lips?
We plan the shape together. Your doctor will look at the proportions of your lips and face and explain what will suit you. The goal is a shape that looks like a naturally beautiful version of your own lips.
Who should not have lip filler?
Lip filler is postponed during pregnancy and breastfeeding, and if you have an active cold sore or infection on or around the lips. If you get cold sores often, tell your doctor beforehand.
What is the difference between 丰唇, 唇部填充 and 玻尿酸丰唇?
They all refer to lip enhancement. 丰唇 is the general term for lip augmentation, 唇部填充 means lip filling, and 玻尿酸丰唇 specifically means lip augmentation with hyaluronic acid filler, which is the treatment described in this article.
How much does lip filler cost?
It depends on the amount of filler you need, so we give a personalised quote after your assessment. WhatsApp us for a quote.
Ready for lips that look like you, only better?
At Verve Clinic in Petaling Jaya, a doctor will assess your lips, talk through the look you want and plan a natural result that suits your face. Read more about our lip filler treatment, or WhatsApp us to arrange your assessment.
About the author
Dr. Adriene Chee is the Medical Director of Verve Clinic in Petaling Jaya. She has more than 10 years of experience. Her qualifications include an MD from the National University of Malaysia (UKM), a Postgraduate Diploma in Dermatology (Bangkok) and an LCP in Aesthetic Medicine. Meet our team.
This article is general information, not medical advice. Results vary from person to person. Please discuss the benefits and risks of any treatment with a qualified doctor.
