Medical Encyclopaedia › Filler (short definition)
In brief: In wrinkle treatment with fillers, a filling material (filler) is injected into or under the skin to smooth wrinkles or compensate for lost volume. Cross-linked hyaluronic acid is used most often. The effect is temporary and, like any injection, the treatment involves risks, which can rarely also be serious.
Which fillers are there?
- Hyaluronic acid: a substance similar to the body’s own that binds water; thanks to chemical cross-linking, it usually lasts several months to about a year in the tissue, sometimes longer in areas with little movement. It can be dissolved with the enzyme hyaluronidase.
- Biostimulators such as calcium hydroxylapatite or poly-L-lactic acid: they not only fill but also stimulate collagen formation; the effect builds up more slowly and often lasts longer. They cannot be dissolved in a targeted way.
- Permanent fillers (for example with non-degradable plastic particles) are viewed predominantly critically by professional bodies because of late-onset nodules and inflammation.
What are fillers used for?
Typical treatment areas are nasolabial folds, marionette lines, lips, cheeks, chin, jawline and tear trough. Fillers work mainly on wrinkles and hollows caused by volume loss. Expression lines, such as frown lines, tend to be treated with botulinum toxin, which dampens muscle activity; both procedures are sometimes combined. Fine crinkly lines and skin quality can only be improved to a limited extent with fillers.
Procedure
Before treatment, there is a discussion about wishes, pre-existing conditions, medicines and previous injections, as well as information about risks and alternatives. The injection is given with a fine needle or blunt cannula, often with an anaesthetic in the preparation. It usually takes only a few minutes to half an hour. Afterwards, saunas, strenuous sport, alcohol and massage of the treated areas should be avoided for one to two days.
Side effects and complications
- common: redness, swelling, tenderness and bruising for a few days
- palpable nodules, irregularities or a bluish sheen if placed too superficially (Tyndall effect)
- infections and flare-up of cold sores
- delayed inflammatory reactions or granulomas, sometimes months after treatment
- rare but serious: vascular occlusion by filler in a blood vessel. Warning signs are severe pain, whitish and later bluish-mottled skin, or visual disturbances during or shortly after the injection. This is an emergency: with hyaluronic acid, hyaluronidase is injected immediately; with visual disturbances, emergency ophthalmological help is needed at once.
Regions rich in blood vessels such as the nose, forehead, glabella and nasolabial area are particularly at risk.
Who is the treatment not suitable for?
It is advised against during pregnancy and breastfeeding, with active skin infections in the treatment area, known allergy to ingredients and, after individual consideration, certain autoimmune diseases or clotting disorders. Anyone taking anticoagulants should say so but not stop them on their own initiative.
Important to know
In the EU, fillers are subject to the rules of the Medical Device Regulation as medical devices or as products without an intended medical purpose. Filler injection is a medical activity and belongs in qualified medical hands that can also recognise and treat complications. You should ask for the product name and batch number and have them documented. Wrinkle treatment with fillers is paid for privately; time to reflect and realistic expectations are important, because the result is limited in time and regular repetitions add up costs and risks.
Related terms in the encyclopaedia
Filler, Hyaluronic acid, Hyaluronidase, Biostimulators, Poly-L-lactic acid, Vascular occlusion after filler, Nasolabial fold, Tear trough, Botulinum toxin
Sources
- U.S. Food and Drug Administration (FDA): Dermal Fillers (Soft Tissue Fillers) – Informationen zu Anwendung und Risiken
- Verordnung (EU) 2017/745 über Medizinprodukte (MDR), Anhang XVI: Produkte ohne medizinische Zweckbestimmung, u. a. Dermalfiller
- DeLorenzi C.: New High Dose Pulsed Hyaluronidase Protocol for Hyaluronic Acid Filler Vascular Adverse Events. Aesthet Surg J 2017
- Bundesinstitut für Arzneimittel und Medizinprodukte (BfArM): Informationen zur Meldung von Vorkommnissen mit Medizinprodukten
Note: This article is for general information and does not replace advice, diagnosis or treatment from a doctor, dentist or pharmacist. Last updated: October 2026.