The variety of injectable products used in medical aesthetic procedures
Hyaluronic acid : filler injections
Hyaluronic acid is, the most widely used product for aesthetic injections. Naturally present in our bodies, particularly in the dermis, cartilage and synovial fluid, it plays a fundamental role in tissue hydration, elasticity and regeneration.
The hyaluronic acid gels used in aesthetics are synthetic, sterile, absorbable, viscoelastic products available in different viscosities depending on the indication : filling superficial wrinkles, restoring deeper volume, hydrating the skin, etc.
Hyaluronic acid is indicated to :
- Correct static wrinkles (nasolabial folds, marionette lines, fine lines around the mouth).
- Restore lost volume (cheekbones, temples, tear troughs, jawline).
- Plump the lips.
- Correct certain asymmetries or post-traumatic depressions.
- Perform a non-surgical facelift.
- Intensively hydrate the skin.
Depending on the density of the gel, its cross-linking (level of cohesion), and the injection depth, the effects can last between 10 and 15 months, sometimes longer.
Botulinum toxin : treatment of expression lines
Botulinum toxin is a purified protein-based medicine whose function is to temporarily block nerve transmission between the motor nerve and the muscle, thereby preventing the latter from contracting. Used at very low doses, it is entirely safe for aesthetic injections.
It is primarily indicated for treating expression lines in the upper third of the face, namely forehead lines (frontalis muscle), frown lines (corrugator and procerus muscles), and crow’s feet (orbicularis oculi).
The effects appear between 3 and 7 days after the injection, with an optimal effect at 15 days, and an average duration of action of 4 to 6 months. Unlike hyaluronic acid, botulinum toxin has no volumising effect, but acts by preventing the formation of skin wrinkles linked to repeated muscle movements.
Its use requires a thorough understanding of facial muscle anatomy, as a poorly performed injection can cause asymmetry, a drooping eyebrow, a drooping eyelid and many other complications.
Botulinum toxin is also used to treat primary axillary hyperhidrosis.
Tissue stimulators : stimulating natural collagen production
Unlike conventional fillers, collagen stimulators (also called biostimulators) are not intended to fill immediately, but to restart endogenous collagen production, thereby improving skin density and firmness over the long term.
The main products in this category are calcium hydroxyapatite, poly-L-lactic acid, and polycaprolactone.
These substances are injected deeply (subcutaneously, or even above the periosteum) and often require several sessions spaced apart, with results developing gradually over 2 to 3 months and lasting up to 2 years.
They are used in particular for moderate sagging of the lower face, tightening the neck, and subtly restoring volume in patients who do not want immediate filling.
Skinboosters : deep skin hydration
Skinboosters represent another use of lightly cross-linked hyaluronic acid, sometimes combined with vitamins, amino acids or antioxidants. Injected in small doses into the middle or superficial dermis, they hydrate the skin from within and improve its quality, radiance and firmness.
These treatments do not affect facial volume. They are particularly suitable for dehydrated or mature skin, and can be injected into the face, neck, décolletage or backs of the hands. They also offer an interesting preventive approach to skin ageing, from the age of 30 to 35.
Platelet-rich plasma (PRP) : autologous biostimulation
PRP is an entirely natural product prepared from the patient’s own blood, which is centrifuged to extract concentrated platelets rich in growth factors. These stimulate cell regeneration, microcirculation and collagen synthesis.
PRP is used in aesthetics for overall skin rejuvenation, treating vascular dark circles, improving skin quality, and even stimulating hair growth in cases of alopecia.
It does not replace fillers, but offers a useful complement for improving tissue quality.
Strictly regulated products : traceability, certification and safety
All products injected for aesthetic purposes must be :
- Sterile, injectable and absorbable, unless specifically indicated otherwise.
- CE marked (European Conformity) or approved by Swissmedic in Switzerland.
- Recorded in the patient’s file with the batch number, injection date and location.
The doctor is responsible for choosing products from recognised laboratories, avoiding uncertified generics, and strictly observing storage, preparation and administration conditions.
Choosing a product for the individual
There is no « best product », but a product suited to each indication, each anatomy, each need, and each skin type. This is why a prior medical consultation is essential : it allows the doctor to make a precise aesthetic diagnosis, analyse volume, skin quality and dynamic imbalances, and choose the most appropriate product in the smallest sufficient quantity.
As part of a comprehensive approach, it is common to combine different types of injections within the same treatment plan (for example : botulinum toxin in the forehead, hyaluronic acid for folds, and Skinbooster for the neck). This combined strategy achieves a more natural, gradual and lasting result.
Permanent fillers : products that are now prohibited
In the history of medical aesthetic procedures, certain so-called « permanent » products were used for many years, particularly those based on polymethyl methacrylate (PMMA) or injectable silicone. These non-absorbable substances promised lasting, or even permanent, correction. However, their use led to severe and unpredictable complications, often several years after the injection : inflammatory granulomas, product migration, nodules, chronic infections.
In Switzerland, as in most Western countries, these products are now prohibited, and their use is considered contrary to good medical practice. Any injection of a non-absorbable substance for aesthetic purposes carries a high risk.
This is why the only products authorised today are absorbable, biocompatible and biodegradable products whose safety has been widely demonstrated.
Injectable product formulation : purity, concentration, cross-linking
When discussing injectable products, knowing their generic name (hyaluronic acid, botulinum toxin, etc.) is not enough. Their physicochemical characteristics must also be considered, as these directly influence the aesthetic result, duration of action and risk of complications.
For hyaluronic acids :
- Concentration (mg/mL) : the higher it is, the denser the product and the more suitable it is for deeper areas.
- Cross-linking : a highly cross-linked hyaluronic acid will be firmer and better suited to structural areas (cheekbones, chin), whereas a lightly cross-linked gel will be used for fine wrinkles .
- Manufacturing technology : certain ranges (Vycross®, RHA®, NASHA®) offer specific formulations that adapt to facial dynamics.
For botulinum toxin :
- The different brands vary slightly in molecular weight, degree of protein complexation, and behaviour in vivo. An experienced doctor will know how to choose the most appropriate toxin according to the indication, the anatomy of the patient’s muscles, and the desired duration.
Additional substances : vitamins, amino acids, antioxidants
In certain protocols, injections combine different active ingredients whose role is not to alter volume, but to provide the skin with deep nourishment, protection and revitalisation. This type of treatment is called aesthetic mesotherapy or biorevitalisation. The injected substances may include :
- Vitamin C : antioxidant, brightening.
- B vitamins : cofactors in cell regeneration.
- Amino acids : precursors of collagen and elastin.
- Trace elements : zinc, copper, manganese, involved in enzymatic reactions.
- Coenzymes : activators of local metabolic activity.
These products are generally administered through multiple small superficial injections, particularly in the face, neck, décolletage and hands. They do not affect volume, but improve skin radiance and quality as part of a comprehensive treatment plan.
