Patient case · in the doctor's own words
ONDA 40kJ on the Stomach in Seoul: Priscilla's First Session and What 40kJ Actually Means
Priscilla (@priscillathach) filmed her first ONDA 40kJ session on the stomach, paired with fat-dissolving injections. Her doctor explains what the kJ number means, what the first weeks look like, and the price.
Explained by
Dr. Hyunji Kim
Director · Lead Physician · Lifting, Laser & Anti-aging
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The number in Priscilla's caption, 40kJ, is the detail people message me about most after a reel like hers. I'm Dr. Hyunji Kim, director of Delphic Clinic beside Sinnonhyeon Station in Gangnam, trained at Korea University Medical Center, and I see and treat international patients myself. This was Priscilla's first session, filmed the day she had it, and she was careful to say results develop over the following weeks. So this page stays on that first day: what 40kJ means, why it was paired with injections, what the first weeks look like, what it costs, and who should not book it.
Medically reviewed · Dr. Hyunji Kim ·
In her own words
Can this replace a tummy tuck? Here’s what I tried🫣 ✨ ONDA 40kJ + Fat Dissolving Injections ⏳ Results develop over the next few weeks
What “40kJ” actually tells you
kJ is the total energy delivered across the treated area during the session. It isn't a strength setting you pick from a menu like a coffee size; it's a budget that I spread across the abdomen, with more passes where the fat is thicker and fewer where it's thin.
On our menu, ONDA body comes in 40kJ and 60kJ for one area. 40kJ is a sensible first session for a single area like the stomach. 60kJ is for larger or thicker areas, or for a patient who has already seen how their body responds.
Why injections were added on the same day
ONDA's Coolwaves microwaves, from DEKA in Italy, heat the fat layer evenly while keeping the surface cool. That suits a broad area. But many stomachs have one fuller pocket, often below the navel, that benefits from a more targeted approach.
A body fat-dissolving injection puts fat-dissolving and circulation-supporting ingredients directly into that pocket in about 10 minutes. I explain the device in more detail in my guide on ONDA for skin tightening and stubborn fat.
How the first day feels
During ONDA, most people describe deep warmth spreading under a cool surface, with brief hotter moments over thicker fat. The injections sting and feel like pressure. Neither needs anaesthetic injections, and I check in throughout.
Afterwards you can walk out and carry on. The abdomen may feel warm, tender or a little swollen, and bruising can show at injection points. Loose clothing helps for the first couple of days.
What her first session costs on our menu
Prices are public, and visitors pay the same as Korean patients. The usual first-visit version of Priscilla's plan, ONDA body 40kJ plus our premium Body Sculpting injection, is:
- Onda Lifting (Body 1 Area) 40kj (First-visit trial)₩270,000≈ $200
- Body Sculpting Injection 10cc (Premium Fat Dissolving)₩129,000≈ $90
VAT excluded · identical for Korean and international patients · regular price for ONDA body 1 area 40kJ is ₩400,000 · the injection type and amount are confirmed at the free consultation, so this is the typical first-visit version of the plan, not Priscilla's exact bill.
Our steroid-free Body Girl Group injection costs ₩99,000 if that suits you better. For more planning, see the ONDA trip budget calculator and the fat-dissolving injection cost map by area.
“Over the next few weeks”: what to watch for
- Week one: swelling and tenderness settle. Don't measure your waist yet; swelling hides change.
- Weeks two to six: any reduction in the fat layer tends to show gradually as the body clears treated cells.
- Take photos in the same light and pose each week; tape measures and mirrors mislead.
- Some patients plan a second session after reviewing photos with me.
Planning the session into a trip
- 1
Send a photo first
Message us on WhatsApp with a standing photo of the stomach from the front and side. I'll tell you whether 40kJ, 60kJ or something else fits.
- 2
Book early in the trip
That leaves a few days to settle any tenderness before a long flight.
- 3
On the day
Consultation with me, then same-day treatment if we agree. English and Chinese interpreters are on site, near Sinnonhyeon Station Exit 3.
Is this for you?
Who this combination genuinely suits
Signs it may be time
- A lower-belly bulge stays the same despite exercise
- You've looked into a tummy tuck but aren't ready for surgery
- Waistbands dig in more than they used to
- You'd like to try a single area before committing to more
A good fit if
- You have a pinchable layer of fat on the stomach, with or without mild laxity
- You want a non-surgical start and can wait weeks to judge the change
- Your weight is fairly stable
- You're open to more than one session if photos suggest it
Not the right first step if: you're pregnant or breastfeeding, have a pacemaker or metal implants in the area, have significant hanging skin or separated abdominal muscles after pregnancy, or need overall weight loss; a surgeon or a different plan is the honest answer in those cases.
“Send me a front and side photo of the area before you travel. I'll tell you whether ONDA is worth trying for your stomach, and whether 40kJ is the right place to start.”
Questions patients ask me about this
What does 40kJ mean for ONDA?
kJ is the total energy delivered across the treated area in a session. At Delphic Clinic, ONDA body comes in 40kJ and 60kJ for one area; 40kJ is a common first session for a single area such as the stomach.
How much is ONDA for the stomach in Korea?
At Delphic Clinic, ONDA body 1 area 40kJ is ₩270,000 at the first-visit price and ₩400,000 regularly, with 60kJ at ₩390,000 first-visit (VAT excluded). International patients pay the same as Korean patients.
Can ONDA replace a tummy tuck?
Not for everyone. ONDA works on fat and mild laxity, while hanging skin or separated muscles usually need surgery. A doctor should assess your abdomen before you choose.
When will I see ONDA results on my stomach?
Change tends to show gradually over several weeks as the body clears treated fat cells. Swelling in the first week can hide early change, so weekly photos are more reliable than the mirror.
Is there downtime after ONDA and fat-dissolving injections on the stomach?
Most people return to normal plans the same day. Warmth, tenderness, mild swelling or bruising at injection points can last a few days.
Get a free 1:1 consultation
Message our English-speaking team — same price as locals, no pressure.
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