STYLAGE® L BI-FLEX®

STYLAGE® L BI-FLEX® is a cross-linked HA filler manufactured by Laboratories VIVACY in France. It is also known as BI-soft and uses IPN-Like Technology™ with BI-FLEX® rheology. The formulation contains 24mg/g hyaluronic acid and 9mg/mL mannitol, without lidocaine. The STYLAGE® range is CE-marked for use in the EU, subject to local regulatory requirements.

STYLAGE® L BI-FLEX® is used for deep wrinkle correction, including nasolabial folds, marionette lines, and glabellar lines, as well as facial volume restoration and contouring. Its use depends on the treatment area, injection depth, product labeling, and condition of the patient’s skin. Administration should be limited to trained aesthetic professionals.

The primary difference is that STYLAGE® L BI-FLEX® does not contain lidocaine, while STYLAGE® L BI-FLEX® with Lidocaine includes 3mg/mL lidocaine co-formulated within the gel for injection comfort. Both products share the same 24mg/g HA concentration, mannitol content, and IPN-Like Technology™. Practitioners who prefer to manage anesthesia independently may find the lidocaine-free formulation more appropriate for their clinical workflow.

STYLAGE® products are CE-marked and clinically used in professional aesthetic medicine. The STYLAGE® L BI-FLEX® formulation incorporates IPN-Like Technology™ for cohesivity, mannitol as an antioxidant to support HA longevity, and BI-FLEX® rheology for versatile use across multiple treatment areas and injection planes. Suitability for a specific patient or indication should be determined by the practitioner’s assessment based on the treatment area, anatomy, and clinical objectives.

The STYLAGE® range is CE-marked for use in the EU, but the current US FDA status should be verified before procurement or administration. FDA approval for dermal fillers is product- and indication-specific. Practitioners should confirm jurisdiction-specific regulatory status before clinical use.

Common side effects include bruising, redness, swelling, tenderness, pain, itching, or firmness at the injection site. These reactions commonly resolve within a few days. Worsening pain, change in skin color, blanching, livedo, or visual symptoms require urgent clinical evaluation.

BI-soft is an alternative name for STYLAGE® L BI-FLEX®, used for practitioner and procurement reference. It reflects the product’s BI-FLEX® optimized rheological profile, which is designed to support smooth, controlled injection across multiple treatment areas and injection planes. The name does not refer to a separate formulation or product line.

Citations

1. Converset-Viethel S, Dobosz M, Baspeyras M, Skretkowicz-Szarmach K, Schlaudraff KU. Effectiveness and Safety of STYLAGE® L Lidocaine in the Treatment of Nasolabial Folds (NICE Study): A Randomized, Double-Blind, Split-Face Controlled Study. Aesthetic Plast Surg. 2025;49(24):6846-6857. doi:10.1007/s00266-025-05105-2
2. Tran C, Carraux P, Micheels P, Kaya G, Salomon D. In vivo bio-integration of three hyaluronic acid fillers in human skin: a histological study. 2014;228(1):47–54. doi:10.1159/000354514
3. Ramos-E-Silva M, Fonteles LA, Lagalhard CS, Fucci-da-Costa AP. STYLAGE®: a range of hyaluronic acid dermal fillers containing mannitol. Physical properties and review of the literature. Clin Cosmet Investig Dermatol. 2013;6:257-261. Published 2013 Oct 23. doi:10.2147/CCID.S35251

The contents of this page are meant for licensed medical professionals. They serve informational purposes only and are not to be taken as medical advice.