By LIV Clinic · Medically reviewed by Dr. Narathai Vichienkalayarut, M.D. · Published August 19, 2026

Radio waves or sound waves? The answer depends on how deep your loose skin actually goes.

Is Thermage or HIFU better for loose skin? Neither is universally better — they treat different depths. Thermage uses radiofrequency to heat a broad area of dermis, suiting crepey, surface laxity, while HIFU uses focused ultrasound to reach deeper layers including the SMAS, suiting deeper sagging and lifting.

The core difference: depth and heat pattern

Thermage heats broadly

The Cleveland Clinic describes radiofrequency using electromagnetic waves to generate heat through the skin’s layers. Thermage spreads this bulk heat across an area of dermis.

HIFU heats deep points

HIFU focuses ultrasound into precise points at set depths, including around 4.5mm — the SMAS layer that surgeons lift.

Which suits which kind of loose skin

Surface and crepey laxity → Thermage

If your concern is thin, crepey or generally slack skin across an area, broad dermal heating suits it well.

Deeper sagging → HIFU

If your concern is a softening jawline, early jowls or drooping that needs lifting from a structural level, focused ultrasound reaches deeper.

Head to head

The clinical literature notes both HIFU and RF effectively treat sagging skin by delivering energy that prompts tissue remodelling.

What they have in common

Both Thermage and HIFU:

• Are non-invasive with no needles
• Have essentially no downtime
• Work by stimulating your own collagen
• Build results gradually over months
• Suit mild to moderate laxity, not severe sagging
• Need periodic maintenance

Comfort and sessions

Sensation

Thermage delivers brief pulses of heat, while HIFU feels like a warm tingling. Both are generally well tolerated, and settings are adjusted for comfort.

How many sessions

Thermage is often a single session with results building over months; HIFU for the face is often one session with yearly maintenance.

When both is the answer

Different layers, complementary

Because they work at different depths, some people benefit from combining them — HIFU for structural lifting and RF for surface quality.

Planned by your doctor

Timing and spacing are decided individually so the treatments complement each other.

What neither can do

Not a facelift

For heavy, advanced laxity, neither matches a surgical facelift, and honest candidate selection matters for both.

Not instant

Both build gradually — if you need an immediate lift, a thread lift may suit better.

Choosing between them

To decide which suits your loose skin:

1. Have a consultation so Dr. Narathai can assess your laxity and its depth.
2. Identify whether your concern is surface crepiness or deeper sagging.
3. Discuss how quickly you want results.
4. Consider whether combining suits you.
5. Agree realistic expectations for a gradual change.
6. Plan maintenance to sustain the result.

Thermage and HIFU at LIV Clinic Koh Samui

At LIV Clinic, both Thermage and HIFU are doctor-led by Dr. Narathai, who will recommend the right one — or both — for your skin. Book a consultation to find out which suits you.

Frequently asked questions

Safety and consultation

Thermage and HIFU is a non-invasive, energy-based medical procedure and, like any device treatment, carries some risk — common temporary effects can include redness, mild swelling, tingling or tenderness, and less common reactions are possible. Results vary from person to person, and no specific outcome can be promised. This article is general information, not medical advice.

At LIV Clinic, every treatment begins with an in-person assessment by Dr. Narathai Vichienkalayarut, M.D., who reviews your skin, medical history and goals before recommending a personalized plan. Book a consultation to find out whether this treatment suits you.