Facial Fillers: Complete Clinical Guide
Hyaluronic acid, 8 treatment zones, cannula technique, real recovery and absolute contraindications. Everything the Cosmo Clinic medical team evaluates before any filler treatment.
Facial filler is not a beauty product. It is medicine. Injectable hyaluronic acid restores volume, defines structure and corrects static wrinkles — whenever the doctor understands precisely where to place it, how much to place, and which product to use.
What is injectable hyaluronic acid
Hyaluronic acid (HA) is a molecule produced naturally by the body, present in the skin, joints and eyes. With age, production decreases: the skin loses thickness, the face loses volume, folds deepen. Injectable HA replaces and restores what time has taken away.
Unlike botulinum toxin, HA does not act on the muscles. It acts on the soft tissues: it fills folds, defines edges, adds projection and deep hydration. The effect is immediate and reversible — the product can be dissolved with hyaluronidase at any point.
In Portugal, the cross-linked hyaluronic acid products approved by INFARMED most used at Cosmo Clinic are: Juvéderm® (Allergan), Restylane® (Galderma) and Belotero® (Merz). Each range includes products with different viscosities and G-prime values — selected according to the zone and objective.
Hyaluronic acid does not create a new face. It restores the volume and structure the face already had. When the result looks natural, that is because it was done well.
How it works in the tissues
The HA used in aesthetic medicine is cross-linked — chemically treated to resist enzymatic breakdown and last months in the tissues. Two properties determine each product's behaviour:
- G-prime (elastic modulus): measures the firmness of the gel. High G-prime = stiffer product, ideal for structural support (jawline, chin, cheeks). Low G-prime = more fluid gel, ideal for delicate zones (lips, tear trough, superficial wrinkles).
- Cohesivity: measures the tendency of the gel to remain together. Highly cohesive product migrates less but has less diffusion area — suited to localised volumes. Less cohesive product distributes more evenly — suited to diffuse hydration.
The doctor selects product and viscosity by zone and objective. Lips treated with high G-prime feel artificial and hard. Jawline treated with low G-prime cannot sustain structure. Calibrating the selection is the doctor's technical work — it is not a decision the patient should make.
Cross-linked HA is gradually metabolised by skin fibroblasts (endogenous hyaluronidase). Duration depends on the zone (mobility, vascularity), the product and individual metabolism — between 6 and 18 months depending on the area.
Exclusive Protocol
The Cosmo Method for Facial Fillers
Natural results and safety in every treatment, regardless of which clinic doctor performs it. Four standardised pillars.
Clinical photographs at rest, front and profile, before any application. Facial proportion analysis (rule of thirds, golden lip ratio) to define realistic objectives.
Each zone receives the product with the appropriate viscosity and G-prime. Lips, tear trough and superficial wrinkles require different products from those used for jawline, cheeks or temples.
The cannula has a blunt tip — it does not cut vessels. Fewer entry points, lower risk of bruising and haematoma. Preferred over needle for folds, cheeks, temples and jawline.
Assessment when swelling has resolved and the product has integrated. The doctor verifies symmetry, natural appearance and whether fine-tuning is needed. Included in the price of all sessions.
Treatment zones at Cosmo Clinic
Hyaluronic acid treats static wrinkles (visible at rest) and volume loss. Dynamic wrinkles (caused by muscle movement) require botulinum toxin. We frequently combine both in the same session.
Volume and definition zones:
- Lips — volume, vermilion border definition, deep hydration, symmetry. The most requested zone. Low G-prime product for a natural texture.
- Cheeks — restoring malar volume lost with age. Defines facial contour and creates an indirect lifting effect.
- Chin — projects and defines the chin, balances the facial profile. Non-surgical alternative to a chin implant.
- Jawline — defines the mandibular angle, slims the facial oval, reduces lower-third laxity. High G-prime product for structural support.
- Temples — restores hollow temporal volume. Common in patients over 40. Improves facial third balance.
Fold and wrinkle zones:
- Nasolabial folds — the creases running from the nose to the mouth corners. Corrected with medium-viscosity product injected deep.
- Marionette lines — vertical folds from the mouth corners to the chin. Give a downturned expression. Corrected with a combination of filler and toxin on the depressor labii.
- Tear trough — high technical complexity zone. Requires very low G-prime, highly cohesive product. Risk of Tyndall effect if the wrong product or incorrect placement is used.
Additional zones:
- Non-surgical rhinoplasty — corrects nose irregularities without surgery. Tip elevation, dorsal hump reduction. Alternative to rhinoplasty.
- Perioral lines (barcode) — vertical lines above the upper lip. Combination of superficial filler with lip toxin.
- Ear lobes — restores volume and firmness to the ear lobe, especially for those who wear heavy earrings.
Cosmo Clinic Protocol
Pre-treatment — what to do before
- Avoid anticoagulants (warfarin, heparin, preventive aspirin) and NSAIDs (ibuprofen) for 5 days before — these significantly increase the risk of bruising. Always confirm with your prescribing doctor.
- No dental treatment in the 2 weeks before (the dentist injects local anaesthetic that can affect the lip and jaw zone).
- No needle facial procedures (mesotherapy, deep peels) in the 2 weeks before.
- History of recurrent cold sores: inform the clinic — we prescribe antiviral prophylaxis before lip filler.
- Good hydration in the days before — improves tissue quality and product integration.
- In-person assessment consultation mandatory — we never treat without seeing and evaluating the patient.
During the session
What happens at the appointment
- Duration: 30-60 minutes depending on the number of zones and volumes.
- Topical anaesthesia (EMLA cream) applied 15-20 minutes in advance — included, no extra charge.
- Cleaning and disinfection of the treatment area.
- Application with cannula (preferred) or fine-gauge needle depending on the zone.
- Gentle massage after application to model and evenly distribute the product.
- Post-application photograph for clinical record and day-14 comparison.
Recovery: what happens day by day
Filler has a different recovery period from Botox. Swelling (oedema) is expected and temporary. Following the post-treatment protocol significantly reduces its intensity and duration.
Post-treatment — protocol by period
First 4 hours (critical phase)
- Ice on the treated zone: 10 minutes ice, 10 minutes rest, repeat. Use ice wrapped in a cloth — never direct skin contact.
- No pressure, massage or manipulation of the area.
- No physical exercise or exertion that increases local blood pressure.
- You can return to normal daily activities immediately.
First 12 hours
- No makeup on the treated zone (infection risk through pores opened by the needle/cannula).
- Sleep with head elevated the first night — reduces accumulated swelling.
First 24-48 hours
- No intense exercise or activities that raise body temperature (sauna, prolonged hot bath).
- No alcohol (vasodilation increases swelling and bruising risk).
- No intense sun exposure or sunbed.
First 2 weeks
- No dental treatment — mandibular movement and local anaesthetic injections can displace recently applied product in the lips, chin and jaw.
- No deep facial massage or ultrasound over the treated area.
- No chemical peel or ablative procedures in the same zone.
Results timeline:
- Immediately after — volume visible but with swelling. Not the final result.
- Days 1-3 — peak swelling (especially lips). There may be apparent asymmetry.
- Days 3-7 — swelling reduces progressively, result begins to stabilise.
- Day 14 — final result. The product has integrated into the tissues. Review appointment.
- Months 6-18 — duration by zone and product (see FAQ).
Bruising is possible, especially in vascular zones like lips and tear trough. It resolves in 7-14 days. Topical arnica can help. It is not a complication — it is a consequence of local vascularity.
Who it's for. Who it's not for.
Hyaluronic acid filler does not solve every aesthetic concern. Being honest about indications and contraindications is part of the Cosmo Clinic protocol.
Main indications:
- Age-related facial volume loss (temples, cheeks, folds).
- Insufficient lip definition and volume.
- Deep static wrinkles (visible at rest) — nasolabial, marionette, perioral.
- Facial volume asymmetries (upper/lower lip, cheeks).
- Jawline, chin or nose definition without surgery.
- Tear trough in younger patients with good skin quality.
When filler is not the answer:
- Significant skin laxity — HA adds volume but does not treat loose skin. Indication for radiofrequency, Ultherapy or surgery.
- Dynamic wrinkles (appear with expression) — indication for botulinum toxin.
- Expectation of permanent results — the effect is temporary by definition.
- Tear trough with prominent fat herniation (fat bags) — filler can worsen this. Indication for blepharoplasty.
Absolute contraindications
- Pregnancy and breastfeeding
- Allergy to hyaluronic acid, lidocaine or product components
- Active autoimmune diseases (lupus, scleroderma, Sjögren's syndrome)
- Therapeutic anticoagulation without prescribing doctor's authorisation
- Active infection or inflammation at the treatment site
Fillers vs Botulinum Toxin: when to use each
The most common question at the first consultation. In summary:
HA Filler
- Static wrinkles, volume loss
- Lips, folds, cheeks, tear trough, chin
- Result: 6-18 months
- Mechanism: adds volume
- Reversible with hyaluronidase
Botulinum Toxin
- Dynamic wrinkles (by movement)
- Forehead, glabella, crow's feet
- Result: 3-5 months
- Mechanism: relaxes the muscle
The two treatments complement each other. The most common combination at Cosmo Clinic is lip or fold filler combined with toxin on the glabella and forehead — in a single session, with the standard sequence: toxin first, filler second. See the botulinum toxin guide for the inverse perspective.
No-obligation assessment
Not sure which treatment is right for you?
The initial consultation is free. The Cosmo Clinic team assesses your facial proportions and recommends the appropriate protocol before any application.
Book Free ConsultationFrequently asked questions
How long do hyaluronic acid fillers last?
It depends on the zone and the product. Lips: 6-9 months (high mobility consumes product faster). Cheeks, jawline, temples: 12-18 months. Nasolabial folds and marionette lines: 9-12 months. Tear trough: 9-12 months. With regular sessions the result tends to last longer because some volume is retained between treatments.
Are results immediate?
Volume is visible immediately, but there is swelling in the first 24-72 hours that alters the appearance. The final result is assessed at day 14. Do not evaluate the result the day after — swelling can create the impression of excess that does not exist once it settles.
Do fillers hurt?
Discomfort is manageable. We apply topical anaesthesia (EMLA cream) before any procedure — included in the price. Most fillers are applied with a blunt-tip cannula, which is less painful than a needle and has a lower risk of bruising. For the lips, the most sensitive zone, anaesthesia is applied 15-20 minutes in advance.
Can filler be reversed?
Yes. Hyaluronic acid can be dissolved with hyaluronidase — an enzyme that breaks down the product within hours. This is one of the greatest advantages of HA over permanent materials. Hyaluronidase is always available at Cosmo Clinic. We use it in cases of unwanted results, product migration or vascular complications.
What can't I do after treatment?
First 4 hours: ice 10 min/hour, no pressure on the treated area. First 12 hours: no makeup. First 24h: no intense exercise or alcohol. First 48h: no sauna or prolonged hot baths. First 2 weeks: no dental appointments, no deep facial massage, no needle procedures in the same zone.
Will I be very swollen?
Immediate swelling is expected and temporary. In the lips it can be more pronounced for the first 24-48 hours. In other zones it is generally mild. Applying ice in the first hours and sleeping with the head elevated the first night reduces swelling. The final result is assessed at day 14, never before.
What is the difference between Juvéderm, Restylane and Belotero?
All three are ranges of cross-linked hyaluronic acid approved by INFARMED. The differences lie in cross-linking technology, G-prime and cohesivity, which vary by product within each range. The doctor selects the appropriate product for each zone. The result depends 90% on correct product selection and technique, not on brand.
Who should not have facial fillers?
Absolute contraindications: pregnancy and breastfeeding, allergy to HA or lidocaine, active autoimmune diseases, therapeutic anticoagulation without prescribing doctor's authorisation, active infection at the treatment site. Relative contraindications: history of recurrent cold sores (antiviral prophylaxis required), recent dental work, recent needle procedures in the same zone. Medical assessment mandatory before any application.
Verified Credentials
ERS Licence
Lic. n.º 25805/2025
Clinic Registration
INFARMED E177515
Medical Director
Dr. Jose Lotario Sousa da Cunha Santos · Lic. n.º 68381
Regulation
INFARMED · Ordem dos Médicos
Next step
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The first consultation is free. The Cosmo Clinic team assesses your facial proportions and defines the protocol before any treatment.