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Procedure guide · Skin and non-surgical
Dermal fillersDermal fillers are injectable gels, usually hyaluronic acid, that restore lost volume in the cheeks, temples and under-eyes, define the lips, jawline and chin, or soften deep folds. A treatment takes twenty to forty-five minutes with numbing cream or a local anaesthetic in the product, and results are immediate. Hyaluronic acid fillers last six to eighteen months depending on the area and product and can be dissolved with hyaluronidase if needed. Injection into an artery is the serious risk, so the injector's anatomical training matters.
Fillers add volume where the face has lost it or never had it. Cross-linked hyaluronic acid gels come in different firmness: soft gels for lips and under-eyes, firmer ones for cheeks, chin and jawline. They are injected with a needle or a blunt cannula into precise planes, and because hyaluronic acid attracts water, the result softens and integrates over two weeks.
Biostimulatory fillers (calcium hydroxylapatite, poly-L-lactic acid) stimulate collagen over months and last longer but cannot be dissolved. Treatment planning looks at the whole face: restoring the cheek often improves the tear trough and folds more than filling the fold itself.
The firmness of a filler is not a marketing label but a measurable property, and it is what tells an injector where a product belongs. Two properties matter most: G prime (the gel’s elastic modulus, or its resistance to being deformed by pressure and muscle movement) and cohesivity (how strongly the cross-linked hyaluronic acid particles hold together as a single mass rather than spreading sideways through the tissue). High G-prime, highly cohesive gels behave almost like a soft putty: they lift and hold their shape against gravity and muscle pull, which is why they are reserved for structural work laid deep against bone or periosteum along the jawline, over the chin and across the cheekbone. Low G-prime gels flow and mould easily under thin, mobile skin, which is why they are chosen for the lips, the tear trough and fine lines around the mouth, where a stiff gel would sit as a visible lump or move unnaturally when the face animates. Manufacturers reach these different behaviours through proprietary cross-linking technologies, and the same brand typically sells a range of products across the firmness spectrum rather than one gel for every area.
Where a filler is injected matters as much as what is injected, because the face’s arteries do not run in the same plane or position in every zone. The glabella, the nose, the nasolabial folds and the temples sit close to named arteries — the supratrochlear, dorsal nasal, angular and superficial temporal arteries among them — that are small, variably positioned between individuals, and in some areas end in a dead-end connection with the ophthalmic artery that supplies the retina. Injecting filler directly into one of these vessels, or compressing an artery against bone so filler is forced backward into it, is the mechanism behind the rare but serious complication of vascular occlusion, and in the worst reported cases, sudden vision loss. This is why these specific zones are treated with more caution than, say, the cheek body: slower injection, smaller aliquots, frequent aspiration or a blunt cannula instead of a sharp needle, and — most importantly — an injector who has studied facial vascular anatomy in detail and adjusts technique by zone rather than using one method everywhere on the face.
How long a filler lasts, and whether it stays exactly where it was placed, depends on more than brand name. Degree of cross-linking and particle size affect how quickly the body’s own enzymes break the gel down, so a densely cross-linked product in a still area like the chin or jawline commonly outlasts a lightly cross-linked product in a constantly moving area like the lips, where muscle activity, chewing and speaking accelerate turnover. Hydrophilicity — how much water a gel draws in after injection — also plays a role: a gel that swells can look fuller at two to four weeks than on the day of treatment, which is a normal part of integration and not a sign of overfilling. True migration, where filler visibly moves away from the injection point over months, is uncommon with modern cohesive gels placed correctly, but is more often reported after large volumes placed superficially in thin-skinned areas such as the tear trough, or after repeated top-ups without allowing earlier product to resorb. This is one of several reasons experienced injectors favour smaller, staged volumes over single large-volume sessions in high-risk areas.
Surgeons look for these points at the consultation.
Adults with volume loss, asymmetry or thin lips seeking a temporary, adjustable improvement, with no active skin infection.
Reasons a good surgeon will ask you to wait or choose something else.
Pregnancy and breastfeeding, active acne or cold sores at the site, autoimmune conditions in flare, previous permanent filler in the same area, and known allergy to product components.
Ask your surgeon which technique they recommend for you and why.
Cross-linked HA gels of different firmness for lips, cheeks, jawline and folds.
Calcium hydroxylapatite or poly-L-lactic acid stimulate collagen over months.
A blunt cannula delivers filler through a single entry point.
Step by step, from arrival to discharge.
The injector examines proportions and agrees the areas and volume.
Topical anaesthetic cream or the lidocaine in the filler.
Filler is placed with a needle or cannula in small amounts, checking symmetry as it goes.
Gentle moulding, cold compress and instructions; a review at two weeks.
Frequencies follow published guidance; your personal risk depends on your health and the surgeon.
Most people who have dermal filler experience nothing worse than the bruising and swelling expected from any needle procedure, and these settle within days without treatment. The odds of a more serious problem rise with the volume injected, the density of blood vessels in the area treated (the lips, nose, glabella and tear trough carry more risk than the cheek body or jawline), and the experience of the injector, since recognising the earliest signs of a complication and acting within minutes — not hours — is what limits lasting harm. Reputable clinics manage this risk at the level of the appointment itself: a documented medical history, a trained medical injector rather than a technician working from a chart, slow and careful technique in higher-risk zones, and hyaluronidase kept on site to dissolve the product immediately if a vessel is compromised. The list below separates what is expected and self-limiting from what is rare but requires same-day medical attention, so you know what to watch for and when to call the clinic rather than wait it out.
For two to five days, more in the lips.
Usually settle or can be massaged or dissolved.
Weeks to months later; treated with antibiotics or dissolution.
Filler blocking an artery causes skin damage or, very rarely, blindness; needs immediate hyaluronidase, which is why an experienced injector with the antidote on site matters.
The first hours after filler are dominated by the numbing wearing off and the treated area feeling tight, tender and slightly swollen — the lips especially can look noticeably fuller than the planned final result for the first two to three days, which is normal and not a sign of overcorrection. Pinpoint bruising is common wherever a needle has passed through small vessels, more so in the lips and under the eyes where the skin is thin, and typically fades over seven to ten days with the help of arnica or cold compresses rather than treatment. Mild asymmetry in the first day or two is also usual, since swelling rarely resolves at exactly the same rate on both sides of the face, and most injectors ask you to wait the full two weeks before judging symmetry or volume. What is not normal, and should prompt an immediate call rather than a wait-and-see approach, is pain that is disproportionate to the injection, skin that turns dusky, mottled or noticeably paler than the surrounding area, or any change in vision — these can be early signs of a vascular problem and are treated as same-day emergencies, not routine side effects to monitor at home.
Day 1
Cold compresses; no makeup for a few hours; avoid alcohol and exercise.
Days 2-5
Lips look larger than the final result at first.
Week 2
Review and adjustments if needed.
Months 6-18
Repeat when the effect fades.
Results are immediate but swollen for two to five days, especially in the lips; the final look settles at two weeks. Hyaluronic acid lasts six to twelve months in the lips and twelve to eighteen months in the cheeks and jawline, then is repeated.
Filler pricing is driven primarily by volume rather than by the area treated: most clinics price per syringe (typically 1 ml), so a subtle lip refinement using half a syringe costs far less than cheek and jawline contouring, which often needs two to four syringes to achieve a visible structural change. Product choice adds a second layer — premium branded hyaluronic acid from established manufacturers costs more than less-studied alternatives, and biostimulatory products such as poly-L-lactic acid are priced per vial and per session rather than per syringe. The injector’s qualifications also factor into the fee: a doctor trained in facial anatomy who can manage a complication safely typically charges more than a technician offering the same product at a lower price.
Why quotes for the same procedure differ, so you can compare packages fairly.
Options to weigh before deciding, surgical and non-surgical.
Permanent volume using your own fat, with a small liposuction.
For dynamic lines rather than volume loss.
A permanent implant when filler is used repeatedly for the chin.
Ask the same questions at every consultation so you can compare answers.
Vascular occlusion is the complication every filler safety protocol is built around, and understanding what it looks like in practice — rather than as an abstract risk on a consent form — is useful for any patient deciding where to be treated. It happens when filler is injected directly into an artery, or compresses an artery against the underlying bone so that the gel is forced backward (retrograde) into the vessel, blocking blood flow to the tissue the artery supplies. The classic warning sign is disproportionate pain at the moment of injection, followed within minutes by blanching: the skin in the affected territory turns strikingly white because blood flow has stopped. As the occlusion evolves over the following hours, the area can develop a mottled, bluish-purple, net-like pattern called livedo reticularis, which signals that tissue is being starved of oxygen.
The reason this is treated as a true emergency, rather than a complication to monitor, is that skin tissue begins to suffer irreversible damage within a few hours of losing its blood supply, and the window for reversing it successfully narrows with every passing hour. The standard response is to stop injecting immediately, apply warm compresses to encourage vessel dilation, massage the area to help disperse the blockage, and inject hyaluronidase — the enzyme that breaks down hyaluronic acid — directly into and around the affected territory in significant quantities, a technique sometimes called “flooding.” Because hyaluronidase dissolves the HA gel rather than the vessel wall itself, restoring flow quickly can prevent permanent skin loss in many cases, which is why it needs to be available in the room, not ordered in after symptoms appear.
The rarest but most serious version of this complication occurs when filler travels backward through an artery as far as the ophthalmic artery, which supplies the retina. This has been reported, almost always after injections in the glabella, nose, forehead or nasolabial fold — areas where arterial connections to the eye’s blood supply are closest — and can cause sudden, severe vision loss in the treated eye within seconds to minutes. Unlike skin necrosis, visual loss from this mechanism is frequently permanent even with prompt treatment, because retinal tissue tolerates oxygen deprivation for only a very short time. This is precisely why the specific injection technique in these danger zones — slow delivery, small aliquots, frequent withdrawal and re-aspiration, and sometimes a blunt cannula rather than a sharp needle — is treated by careful injectors as non-negotiable rather than optional caution.
For a patient, the practical takeaway is simple: before treatment, it is reasonable to ask whether the clinic stocks hyaluronidase on site and has a written protocol for managing occlusion, and after treatment, any disproportionate pain, blanching, mottled skin colour or visual disturbance should prompt an immediate call to the clinic rather than waiting to see if it settles.
Hyaluronidase is an enzyme, derived from bovine or ovine sources or produced as a recombinant human protein, that breaks the chemical bonds holding hyaluronic acid together. Because essentially all modern dermal fillers are built from cross-linked hyaluronic acid, this single enzyme can dissolve almost any HA filler on the market, which is the main reason HA products are considered the safer, more conservative starting point for anyone new to filler: if the result is wrong, it can usually be corrected, rather than simply waited out over many months.
The two most common reasons to use hyaluronidase are at opposite ends of the urgency scale. At the emergency end, it is the frontline treatment for vascular occlusion, injected promptly and in substantial quantity to clear a blocked vessel before tissue is permanently damaged. At the routine end, it is used electively, often weeks or months after treatment, to correct a result the patient or injector is unhappy with: a lump that has not settled with massage, visible asymmetry between the two sides of the face, filler that has migrated beyond its intended boundary, or simply an area that looks overdone. In these elective cases, a small, targeted dose dissolved directly into the area of concern is typical, and the effect is usually visible within 24 to 48 hours.
Hyaluronidase has limits worth knowing before treatment, not after. It only dissolves hyaluronic acid: it has no effect on biostimulatory fillers such as calcium hydroxylapatite or poly-L-lactic acid, and none on permanent fillers, which reputable clinics avoid for this exact reason — once injected, these cannot be chemically reversed. Dissolving a large volume of HA filler can also require more than one session for a complete result, and the area will typically swell again temporarily after the hyaluronidase injection itself before settling. True allergy to hyaluronidase is rare but documented, which is why some practitioners offer a small test dose in patients with a history of bee-sting or insect-venom allergy before a full treatment dose, since the enzyme shares some structural similarity with certain insect venom proteins.
One practical consequence of all this: dissolving filler is not an instant undo button. It takes a follow-up appointment, usually at least a few days to assess properly, and in most cases a short period of swelling before the skin returns to how it looked before any filler was placed. Anyone considering filler while travelling should factor this into timing — if a correction is needed, it is far easier to arrange with a clinic you can return to than with one on the other side of a flight.
A common misconception is that “filler” is one product used everywhere with the only variable being quantity. In practice, most experienced injectors carry several different gels from the same manufacturer’s range, chosen deliberately by area rather than by habit, because the mechanical demands on filler in the cheek are very different from the demands in the lip.
Deep structural areas — the cheekbone, the jawline, the chin and sometimes the temple — need a gel with high lifting capacity and strong cohesivity, so it can be placed in a single deep deposit against bone or deep fat and hold a shape that resists the pull of the muscles layered above it. These products tend to be thicker and are usually injected in small, precise boluses rather than spread in multiple passes. Superficial, mobile areas — the lips, the fine lines around the mouth, and the tear trough beneath the eye — need the opposite properties: a soft, low G-prime gel that spreads evenly under thin skin and moves naturally with expression. Using a cheek-grade product in the tear trough is one of the more common causes of a visibly lumpy, bluish result (sometimes called the Tyndall effect, where light scatters off superficial filler and gives the skin an underlying blue-grey tint), which is why this area in particular calls for a specific low-viscosity product and very superficial, conservative placement.
Delivery method is chosen alongside product. A fine needle gives the most precision for small, superficial placements such as lip border definition, while a blunt-tipped cannula — inserted through a single entry point and then threaded under the skin — is preferred by many injectors for larger-volume areas like the cheek or for zones with a higher density of vessels, because a blunt tip is less likely to pierce an artery than a sharp needle, even though it cannot eliminate the risk entirely.
For a patient, the practical implication is that it is reasonable to ask which specific product is being used in which area and why, rather than assuming “filler” is interchangeable. An injector who can explain the choice by area — rather than defaulting to one syringe type for the whole face — is generally one who has had more structured training in facial anatomy and product rheology.
The look widely described in media coverage as “filler fatigue” or “pillow face” — overly rounded cheeks, lips that look stretched rather than defined, and a loss of the normal light-and-shadow contours of a face — is almost always the cumulative result of repeated top-up appointments over months or years rather than any single treatment. Hyaluronic acid filler does not disappear overnight; it resorbs gradually, and if a new syringe is added before the previous one has fully broken down, volume compounds session after session. Because the change at each individual appointment is often small, patients and sometimes injectors can lose track of how much total volume has accumulated in an area over a few years of regular top-ups.
Two technical features of modern filler make this easier to happen without anyone intending it. First, HA gels are hydrophilic — they draw in water from surrounding tissue over the days and weeks after injection — so a treated area can continue to look fuller for some time after the appointment, which, if repeated before full resorption, nudges the baseline upward each cycle. Second, areas with naturally thin or less elastic skin, such as the lips and under-eyes, show the visual effects of accumulated volume faster and less forgivingly than areas like the cheek, where the surrounding fat pad can absorb some additional volume without changing the surface contour as dramatically.
Avoiding this outcome is less about any single injection technique and more about how treatment is planned over time. Conservative injectors typically favour smaller volumes per session, longer intervals between top-ups, and a standing rule of reassessing the whole face at each visit rather than automatically repeating the previous session’s plan. Baseline photographs taken before any filler is started are a useful anchor for this, since they let both patient and injector compare the current state of the face against the original proportions rather than against the most recent, already-enhanced appointment — a reference point that tends to drift gradually enough to go unnoticed otherwise.
If an overfilled result has already developed, it is reversible with hyaluronic acid products: hyaluronidase can reduce accumulated volume in a planned, staged way, often over more than one session, allowing the face to be brought back toward its natural proportions before any future filler, if desired, is restarted more conservatively.
Filler addresses one specific problem — lost or absent volume — and is frequently combined with treatments that address different problems, because the ageing or asymmetric face rarely has only one issue to correct. The most common pairing is with botulinum toxin, which relaxes the small muscles responsible for dynamic lines such as frown lines and crow’s feet. The two treat different mechanisms and are often performed in the same appointment when treating different areas, such as toxin in the forehead and filler in the cheeks. Where both are intended for the same area — the glabella, for instance — some injectors prefer to treat with toxin first and reassess filler need two or so weeks later, once the muscle relaxation has taken full effect, though many experienced practitioners judge this safely in a single visit.
Biostimulatory treatments — poly-L-lactic acid, calcium hydroxylapatite used in a diluted “skin-booster” technique, or microneedling-based collagen stimulation — target skin quality rather than structural volume, and are commonly layered with HA filler in a staged plan: filler restores the three-dimensional shape first, and biostimulatory treatment improves the quality of the skin draping over that new structure in the months that follow. Because these work on different timelines, the two are usually sequenced across separate appointments rather than mixed in one.
Filler is also often used alongside surgical procedures, either as a non-surgical trial of a look before committing to permanent surgery, or as a complementary refinement after surgery once healing is well established. When filler and a surgical procedure are planned close together, timing matters: most surgeons prefer filler either well before surgery or only after the surgical area has fully healed, both to avoid confusing swelling patterns during recovery and because surgical manipulation of tissue that recently received filler can be technically harder.
As a general rule, any combination plan should be sequenced and explained in advance by whoever is coordinating the treatment, rather than decided reactively during a single appointment — this is particularly relevant for patients travelling abroad who may be combining a consultation, a surgical procedure and aesthetic refinements within one trip, where there is less room to spread treatments across the ideal natural timeline.
Because dermal filler is delivered in a short appointment with no incision and an immediate visible result, it is sometimes treated — by patients and some providers — as a low-stakes, walk-in treatment rather than a medical procedure with a real, if uncommon, risk of serious harm. The qualifications of the person holding the needle are the single biggest factor in that risk, and they vary more between clinics, and between countries, than most patients expect.
Regulation of who may legally inject filler differs by country: in some, only doctors and dentists may perform it; in others, appropriately trained nurses or other allied health professionals may also inject, usually under medical supervision; in a minority of unregulated settings, filler is injected by people with no medical qualification at all. When researching a clinic abroad, it is worth establishing, specifically, who will actually perform the injection, what medical qualification and aesthetic-specific training they hold, and whether a doctor is present or reachable on-site during the appointment in case of a complication. A consultation that genuinely assesses facial anatomy, asks about medical history and allergies, and discusses risk in more than a sentence is a reasonable sign of a properly run clinic; being offered a treatment on demand with no assessment, or being quoted an unusually low price for well-known branded products, are both signs worth treating with caution, since discounted filler can sometimes indicate diluted, counterfeit or unlicensed product, a known problem in some unregulated markets.
The single most important practical question for safety, and one worth asking directly, is whether the clinic stocks hyaluronidase on site and has a clear protocol for recognising and managing vascular occlusion — since, as described above, the difference between a good and a poor outcome in that rare scenario is measured in minutes, not days, and an injector without the antidote in the room cannot act in that window regardless of skill.
Continuity of care is the other consideration specific to travelling for treatment. Most filler complications that need attention present within the first days to weeks, so it is worth understanding, before treatment, what the clinic’s policy is if you are back home when a problem appears: whether they offer remote guidance, coordinate with a local practitioner, or require you to return in person. A credible clinic will discuss this proactively as part of the consultation rather than only when asked, and will give you written aftercare instructions and a direct contact for urgent concerns before you leave.
Hyaluronic acid fillers from established manufacturers, because they can be dissolved. Permanent fillers are not recommended.
HA filler dissolves with hyaluronidase within a day or two. Biostimulatory and permanent fillers cannot be dissolved.
Not usually on its own; the treatment is quick and follow-up matters. It suits patients already abroad for surgery who want a small refinement.
No. The lips move constantly through speaking, eating and expression, which breaks down filler faster than in a still area. Lip filler typically lasts six to twelve months, while cheek and jawline filler, placed deeper against bone in a less mobile area, often lasts twelve to eighteen months or longer. This is also why lip filler needs more frequent top-up appointments to maintain the same look.
True migration — filler visibly shifting away from the injection site months later — is uncommon with modern cohesive gels placed by an experienced injector, but is more often seen after large volumes placed superficially in thin-skinned areas such as the tear trough, or after repeated top-ups layered before earlier filler has resorbed. It is correctable with hyaluronidase.
Filler is a manufactured hyaluronic acid or biostimulatory gel, injected in a short non-surgical appointment and, if HA-based, reversible with hyaluronidase. Fat transfer uses a small amount of your own fat, harvested by liposuction and reinjected, which requires a minor surgical procedure with more downtime but gives a result that is largely permanent and cannot be dissolved if you change your mind.
It can be, provided the clinic is appropriately licensed, the injector is medically qualified, and you understand that most complications — swelling, lumps, early signs of a vascular problem — present within the first days to weeks, while you may already be home. Ask in advance what support the clinic offers remotely or through a local contact if an issue arises after you travel.
True allergy to modern hyaluronic acid filler is rare, since HA is naturally present in the body, but reactions to the local anaesthetic in the product or, occasionally, to hyaluronidase used for dissolving are possible. Signs include unusual swelling, hives, or itching beyond the injection site. Clinics treating a known reaction use antihistamines or, rarely, steroids, and will review your allergy history before any further treatment.
Yes, if it is hyaluronic acid filler. Hyaluronidase dissolves the product, usually with visible improvement within one to two days, and can be used to correct lumps, asymmetry, or an overdone result. Biostimulatory and permanent fillers cannot be dissolved this way, which is one of several reasons HA products are the more conservative, correctable choice for most patients.
No reputable evidence shows that stopping filler leaves skin worse off than before treatment. The area gradually returns to its pre-filler state as the hyaluronic acid resorbs over months. Any sense of looking "different" after stopping is usually the visible return of the original volume loss the filler was correcting, not a new problem caused by the filler itself.
Filler is not usually an absolute contraindication on blood thinners, but bruising and the risk of a larger bruise or swelling are higher, and some injectors prefer to defer treatment or coordinate timing with your prescribing doctor first. Always disclose all medications, including aspirin and over-the-counter anti-inflammatories, which also increase bruising risk even though they are not prescription blood thinners.
Most clinics advise waiting at least until initial swelling has visibly reduced, usually two to three days, before flying, since cabin pressure changes can temporarily increase swelling in a freshly treated area. There is no strict medical ban on flying sooner for a straightforward lip treatment, but most patients prefer to let the initial swelling settle before travelling for comfort and appearance.
Most patients describe it as uncomfortable rather than painful, particularly with topical numbing cream or the local anaesthetic already mixed into most filler products. The lips, being more sensitive, are usually the area patients find most uncomfortable, while the cheeks and jawline are generally better tolerated. A pinching or pressure sensation during injection is typical and brief.
Yes, and demand has grown steadily. Goals typically differ from those common in women: male filler patients more often seek a stronger, more angular jawline, chin projection, or correction of under-eye hollowing, rather than lip volume. Technique and product choice adjust accordingly, usually favouring firmer, structural products over soft, rounding ones, to preserve typically more angular male facial proportions.
The classic early sign is pain clearly out of proportion to the injection itself, followed within minutes by the skin in that area turning noticeably pale or white. This should be reported to the injector immediately, during the appointment if possible — it is treated as a same-day emergency requiring immediate hyaluronidase, not something to monitor overnight.
Clinics generally advise avoiding strenuous exercise, saunas, and alcohol for 24 to 48 hours, since increased blood flow and heat can worsen swelling and bruising. Flying is not strictly prohibited but is usually deferred a few days for comfort, as cabin pressure changes can temporarily increase swelling in the treated area.
Ask the clinic to show you the product box and syringe before injection — legitimate clinics are accustomed to this request and will show the sealed packaging with a batch number and expiry date. Unusually low prices for well-known branded fillers can be a sign of diluted or counterfeit product, a documented problem in some unregulated markets, which is a reason to verify rather than assume.
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