Radiofrequency · Skin Tightening

Thermage FLX

How this page was made
This page was written with AI assistance and reviewed against the sources listed under References below. It is general information only, not medical advice. See our full disclaimer for how SHEA creates and reviews treatment information.
01

What it is

Thermage FLX is a non-invasive radiofrequency (RF) device used for skin tightening and the treatment of wrinkles. RF energy is delivered into tissue while the treatment tip also provides surface cooling.

FLX is the fourth generation of the Thermage system. It includes AccuREP technology, which measures tissue impedance during treatment and adjusts energy delivery. The FLX system received US FDA clearance in 2017 and Korean MFDS approval in 2018.

Much of the published clinical evidence for Thermage comes from earlier generations of the system, including the original ThermaCool device. These studies help establish the clinical history of monopolar RF treatment, but their results should not automatically be treated as FLX-specific outcome data.

02

Why people consider it

  • They are considering a non-surgical treatment for skin laxity or wrinkles
  • They are comparing radiofrequency treatment with other non-invasive tightening technologies such as HIFU
  • They want a treatment that does not involve surgical incisions
03

What the experience is like

The treatment tip is repeatedly applied across the selected treatment area while radiofrequency energy is delivered into the tissue. Thermage combines heating with surface cooling during treatment.

Comfort varies between individuals and according to the treatment area and settings used. Temporary redness, swelling, or other treatment-site reactions can occur.

Changes, when they occur, may develop over time rather than being fully apparent immediately after treatment. The treatment area, number of pulses, settings, and protocol can vary, so ask the clinic what is included in the treatment being offered.

04

Limitations & considerations

  • Much of the published clinical evidence for Thermage was produced using earlier generations of the system rather than the current FLX platform
  • Results vary between individuals, and no specific degree of tightening or wrinkle improvement can be guaranteed
  • The manufacturer lists an implanted pacemaker, automatic implantable cardioverter-defibrillator (AICD), or other implanted electrical device as contraindications to Thermage treatment
  • Thermage has not been studied by the manufacturer in people who are pregnant or breastfeeding, so this should be discussed with the treating clinician
  • Burns, changes in skin surface contour, and other complications have been reported with radiofrequency treatment, although treatment techniques and Thermage device generations have changed over time
  • People with significant skin laxity may not achieve the result they are looking for with a non-surgical treatment
Evidence note
A multicenter study of 86 participants treated with the original ThermaCool system evaluated a single treatment for periorbital tissue tightening. At six months, blinded photographic assessment found at least a one-point improvement in wrinkle score in 83.2% of evaluated treatment areas. However, treating physicians assessing participants without reference to baseline photographs recorded improvement in 28.9% of treatment areas, and 50% of participants reported being satisfied or very satisfied with wrinkle reduction. The study used an early Thermage generation and should not be treated as a direct clinical trial of the current FLX platform.
A separate small histological study examined tissue changes after treatment with an early-generation Thermage RF system. The study included a Thermage-affiliated author, and another author disclosed serving on the company's medical advisory board and receiving research support. These relationships are relevant when interpreting the findings.
Thermage FLX itself received US FDA clearance in 2017 and Korean MFDS approval in 2018. Regulatory clearance and approval establish permitted device uses and regulatory status; they should not be interpreted as proof that every patient will experience a particular cosmetic outcome.

References

Peer-reviewed literature, manufacturer safety information, and regulatory records.

1. Fitzpatrick R, Geronemus R, Goldberg D, Kaminer M, Kilmer S, Ruiz-Esparza J. Multicenter study of noninvasive radiofrequency for periorbital tissue tightening. Lasers in Surgery and Medicine, 2003;33(4):232–242.
Peer-reviewed · Multicenter study (n=86) · Original ThermaCool device
2. Zelickson BD, Kist D, Bernstein E, et al. Histological and ultrastructural evaluation of the effects of a radiofrequency-based nonablative dermal remodeling device: a pilot study. Archives of Dermatology, 2004;140(2):204–209.
Peer-reviewed · Histological pilot study · Early Thermage generation · Industry relationships disclosed
3. Solta Medical. Thermage CPT/FLX System — indications, contraindications, precautions, and important safety information.
Manufacturer · Product safety information
4. US Food and Drug Administration. Thermage FLX System — 510(k) clearance K170758, 2017.
US regulatory
5. Korea Ministry of Food and Drug Safety (MFDS). Thermage FLX System — Import Approval No. 18-245, 2018.
Korean regulatory
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