Medical Encyclopaedia › Lip filler (short definition)
In brief: In lip filler treatment, a filling material – today almost always cross-linked hyaluronic acid – is injected into the lips. The aim can be more volume, a clearer contour, correction of asymmetries or smoothing of fine lines around the mouth. The effect is temporary and, as with any filler injection, there are risks.
How does the treatment work?
Hyaluronic acid is a substance produced by the body that binds water. For fillers, it is chemically cross-linked so that it is broken down more slowly in the tissue. For the lips, softer, flexible preparations are usually used because the mouth is constantly in motion. The body gradually breaks down the material; on the lips, the effect often lasts a few months to about a year, varying greatly from person to person. One advantage of hyaluronic acid is that it can be dissolved again with the enzyme hyaluronidase. Permanent filling materials are not recommended for the lips because of late-onset nodules and inflammation.
Procedure
Before treatment, wishes, facial proportions, previous fillers, allergies, medicines and a history of cold sores are discussed. After disinfection and anaesthesia with cream or a nerve block, the preparation is injected with a fine needle or blunt cannula. Often a conservative approach is taken first, and after about two to four weeks it is assessed whether a small correction makes sense. The treatment itself usually takes only a few minutes to half an hour.
After the treatment
The lips are usually swollen immediately afterwards and can look uneven; the swelling generally subsides within a few days. Bruising, a feeling of tightness and tenderness are common. For the first one to two days, saunas, intensive sport, alcohol and pressing or massaging the lips firmly should be avoided. Anyone prone to cold sores should say so beforehand; sometimes an antiviral medicine is recommended as a precaution.
Risks and complications
- palpable nodules, irregularities or migration of the material beyond the lip border
- over-corrected, unnatural-looking lips, especially after many repeat treatments
- flare-up of cold sores, infections
- delayed inflammatory reactions or granulomas, sometimes only weeks to months later
- rare but serious: vascular occlusion by filler in a labial artery. Warning signs are severe pain, marked pallor, later bluish mottled skin or blisters. This is an emergency that must be treated immediately with hyaluronidase.
Treatments by non-medical staff or with needle-free compressed-air devices (“hyaluron pens”) are considered particularly risky; in Germany, courts classify injection with such devices as the practice of medicine, which laypersons are not permitted to carry out.
Who is it not suitable for?
It is advised against during pregnancy and breastfeeding, in the case of acute inflammation or cold sores on the lips, allergies to ingredients and, after consideration, certain autoimmune or clotting disorders. Anticoagulant medicines should be mentioned but not stopped on your own initiative. Purely aesthetic lip fillers are not appropriate for minors.
Important to know
Lip filler treatment is paid for privately and is a medical treatment that belongs in qualified medical hands. It is advisable to ask about the preparation, batch number and the procedure in the event of complications, and to have written documentation. Images from social media are not a good benchmark: lip shape, tissue and facial proportions set limits. Time to reflect before the first appointment and restraint in the amount used reduce the risk of being dissatisfied with the result.
Related terms in the encyclopaedia
Lip filler, Filler, Hyaluronic acid, Hyaluronidase, Vascular occlusion after filler, Granuloma, Tyndall effect, Marionette lines, Botulinum toxin
Sources
- U.S. Food and Drug Administration (FDA): Dermal Fillers (Soft Tissue Fillers) und Warnung vor nadelfreien Injektionsgeräten für Hyaluronsäure (2021)
- 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.