How many shots — what the number ‘shots’ really is
“What is the difference between 300 and 600 shots?”, “I heard you need 900 shots for it to work” — questions we get often. Follow the source of that number, though, and no clinical trial appears at the end of it. A ‘shot’ is not a dose unit the operator sets but a pulse count sealed in advance into a consumable tip — the US medical device registry records it exactly so: “EYE, 0.25 cm², 450 REP” and “TOTAL, 4.0 cm², 600 REP”. The numbers on the price lists in the market are the specification of the tip that was bought. More striking still is that the endpoint the manufacturer's manual sets for the treatment is not a shot count but “heat feedback of 2.0–2.5 reported by the patient”.
The conclusion, first
A ‘shot’ is not a dose but a specification. One shot in a radiofrequency treatment is one energy pulse, and the total number of them is not set by the operator but fixed in advance and sealed into a single-use tip — the US medical device registry records it exactly so, “EYE, 0.25 cm², 450 REP” and “TOTAL, 4.0 cm², 600 REP”. That the market's “300 · 600 · 900 shot” price lists fall out as multiples and combinations of those specifications is no coincidence. And the endpoint the manufacturer's technical manual gives for the treatment is not a shot count but “until the patient reports heat feedback of 2.0–2.5 on a scale of 0 to 4” — the manual carries no recommended number of shots for the face at all. The answer to the question that actually matters is this. We did not find a study that randomly assigned people to 300 versus 600 shots and compared them. What exists is a histology study in three people, an experiment in pigs delivering 1 · 6 · 12 overlapping shots on one spot, and a survey in which 86.3% of 82 doctors agreed that “900 shots is appropriate”. One more thing at the end — the same 300 shots is a different amount with a different tip. 300 shots with a 3 cm² tip and 300 shots with a 0.25 cm² tip differ twelvefold in nominal area.
What one shot is
A radiofrequency device puts the tip against the skin and passes energy through once for a set time. That one pass is one shot. In English-language material it is written as a REP (radiofrequency energy pulse).
Here is the part most people do not know. That pulse count is sealed into the tip in advance. The tip is a single-use consumable, and once the set number is used up nothing more comes out of it.
| Product listing | Area | Sealed pulse count |
|---|---|---|
| EYE tip | 0.25 cm² | 450 REP |
| TOTAL tip | 4.0 cm² | 600 REP |
So the real meaning of the question “how many shots would you like” is closer to “how many tips would you like to use”. The evidence for that is that the market's 300 · 600 · 900 fall out as multiples of the tip specifications — 900 is usually a tip and a half, or two tips split between areas. This is a consumable unit, not a clinically established dose unit.
XERF likewise has a maximum shot count set per tip — i05 400, i10 300, E40 600, E60 600. What those numbers mean is set out in the four EFFECTOR tips.
The endpoint the manufacturer sets is not a shot count
This will be the most unexpected part of the piece. We went and checked the technical user's manual of a long-established monopolar device.
“Continue to treat, adjusting the Treatment Level setting up or down within the recommended range … until the patient reports heat feedback of 2.0–2.5 on a scale of 0 to 4.”
— keep treating, raising or lowering the output, until the patient reports heat feedback of 2.0–2.5 on a scale of 0 to 4.
That is, the criterion the manufacturer set is not “how many shots” but “what the patient feels”. And within the range in which we checked that manual in full, no recommended total shot count for the face or the body is written in it.
There is one number that does appear in the manual. It is the sentence “the number of REPs delivered varies widely, from 100 to 2000, based on the size and cooling profile of the treatment tip in use”. But look at where that sentence sits and it is in a passage explaining cryogen consumption — it is guidance on managing a consumable, not a clinical recommendation. Rendering it as “up to 2000 shots is possible” is a misreading.
Why the protocol shifted to ‘many passes, gently’
In the early 2000s this treatment was a single pass at high energy. Now it is several passes at low energy. That shift is the background to “shot counts going up”. Take the evidence one piece at a time.
| Evidence | Content | Limit |
|---|---|---|
| Histology study (2006) | A single high-energy pass versus 3–5 low-energy passes, observed by electron microscopy — the collagen change was greater on the multiple-pass side | Three people |
| Physician survey (2007) | “Too painful” on the old method 45% → 5% on the new; tightening at six months 54% → 92% | Not a randomised trial but a recall comparison surveyed from 14 physicians |
| Prospective observation (2007) | Up to 5 passes, a mean of 556 shots, 92% improved at six months | No control group. The instrument-measured objective indices declined over time |
There is something to be precise about here. The point of this shift was not “let us increase the total” but “let us lower the intensity of each delivery and spread it out”. The report of pain falling from 45% to 5% shows that direction well. And yet in the market this story circulates rewritten as “the more shots the better”. They are not the same statement.
Is there a study comparing shot counts, then
We did not find a study in humans that randomly assigned different shot counts and compared them. This is what we did find.
| Source | What was compared | Limit |
|---|---|---|
| Human histology study (2006) | 1 pass versus 3–5 passes | Three people |
| Pig experiment (2026) | 1 · 6 · 12 overlapping shots on the same spot — the 12-shot group had the most collagen and gained it earliest | Not human, and not “how many shots over the whole face” but “how many times overlapped on one point”. Since 12 shots was the highest dose group, we do not know where adding more stops helping |
| Post hoc analysis of an observational study (2007) | Trends by band of shot count | Not randomly assigned. On top of that, the band figures as cited do not match the mean in the original paper, so we have not used this material as evidence |
| Split-face tip size study (2024) | Tip area | Fixed at 300 shots on both sides — shot count was a controlled variable |
In sum, no comparative trial in humans supporting “600 shots is better than 300” exists. The pig experiment suggests a direction, but that is a story about overlapping shots on one point, a different question from the amount of treatment given over a whole human face.
Where did ‘900 shots’ come from
We traced it. It was not a professional society recommendation.
In a 2017 survey of 82 Korean dermatologists, 86.3% agreed with the statement that “900 shots is appropriate for facial tightening in the 35–65 age range”. In a 2020 follow-up survey, most respondents said they preferred the 600-pulse 4 cm² tip.
This is expert opinion, not the result of a comparative trial. The number does not come from material in which 900 shots and 600 shots were tested side by side and 900 came out better; it is a tally of the answer “I think that is about right”. That is not to say expert opinion is worthless — only that it is a different grade of evidence, and in advertising the distinction disappears when it is quoted.
To add one thing, an international Delphi consensus on this treatment (8 experts, 19 recommendations) appeared in 2020, but we were not able to read the full text and so could not confirm whether it contains a shot-count recommendation. The abstract does, however, state that “device specific guidelines are lacking”.
Do more shots mean more side effects
Intuitively you would think so, but there is no study analysing the relationship between shot count and adverse events either. We set down both the material that suggests a direction and the material that points the other way.
| Source | Report | How to read it |
|---|---|---|
| 2003 multicentre study | Second-degree burns 0.36% — 21 events in 5,858 deliveries | The only report whose denominator is a ‘shot’. Taken at face value, shot count is proportional to the number of exposures to a burn. But these are figures from the old high-energy method |
| 2007 large observational study | Second-degree burns 2.7% across 757 treatments, persistent erythema 1.22%, fat atrophy included | The authors recommended “do not stack a shot immediately on the spot just treated” as a guard against overheating |
| Recent studies | Zero adverse events at 600 shots · 36.6 kJ total, zero serious adverse events at 412 shots | With the low-energy multiple-pass method the reports are, if anything, fewer |
So neither “more shots is dangerous” nor “more shots is still safe” can be asserted. What sets the risk appears to be less the shot count itself than the intensity of each delivery, the way shots are overlapped, the cooling, and how the operator responds to the patient's signals.
The same 300 shots is not the same 300 shots
This is the most practical part when you are comparing prices.
| Tip area | Shots | Nominal treated area |
|---|---|---|
| 3 cm² | 300 shots | 900 cm² |
| 4 cm² | 300 shots | 1,200 cm² — 33% wider |
| 0.25 cm² (eye tip) | 450 shots | 112.5 cm² — about 1/10 of 300 shots with the 4 cm² tip |
The areas in the table are nominal values we calculated as tip area × shot count, and in practice 15–30% of the passes overlap, so the area actually covered is smaller than this. The point still holds.
“How many shots” is a number that is not complete unless the tip is named with it. There is no guarantee that “600 shots” at two different clinics is the same amount, and 450 shots for the eyes and 450 shots for the face at the same clinic are entirely different amounts. As far as we know, there is no paper that has addressed this incomparability head on — it is an area where custom has run ahead of academic discussion.
How many shots did the actual studies use
| Study | Tip | Shots | Total energy |
|---|---|---|---|
| 2007 observation | — | Mean 556 shots, up to 5 passes | 83 J/cm² |
| 2022 study | 4 cm² | 412 ± 49 shots, 3–4 passes | 31 ± 4.7 kJ |
| 2024 study | 4 cm² | 600 shots (cheek · lower face 400 · chin 100 · periorbital 100) | 36.6 ± 2.5 kJ |
| 2024 tip comparison | 3 versus 4 cm² | 300 shots each | 16.4 versus 16.6 J/cm² |
| 2025 eye treatment | 0.25 cm² | 225 shots per eyelid · 450 for both eyes, 7–10 passes per eye | — |
What to read in the table is not the numbers themselves but the width of the range. 300 shots and 600 shots both appear in the literature, and no comparison of which is better exists between those papers. The regions, tips and pass counts are all different, so they are numbers that cannot be set side by side in the first place.
So what do we go by in deciding
- We settle the region first. Whether it is a broad surface or a narrow curved one settles the tip, and once the tip is settled the range of shots available follows.
- We start the output low. Rather than going to maximum from the outset, we adjust while checking the temperature response you report.
- The criterion is the response, not the number. Even the manufacturer's manual sets the endpoint by heat feedback. If it feels “hot”, please do not endure it and say so straight away.
- We do not stack shots consecutively on the same spot. That is what the 2007 study recommended explicitly as a guard against overheating.
We do not tell you that “it takes at least so many shots to work”. Because there is no basis for saying it. And equally we do not tell you that “more shots means proportionally better”.
Worth checking in a consultation
- “Which tip, and how many shots?” — a shot count given without naming the tip cannot be compared.
- “Where on the face will those shots be spread?” — the same 600 shots over the whole face and over the jawline alone are entirely different densities.
- “How many passes will it be divided into?” — low energy over multiple passes is the standard method now.
All three are questions the numbers on a price list cannot answer.
In summary
| Confirmed | Could not confirm |
|---|---|
| A shot is a pulse-count specification sealed into a single-use tip | A study in humans randomly comparing shot counts — there is none |
| The manufacturer's endpoint is not a shot count but heat feedback of 2.0–2.5 | A recommended shot count set by a professional society |
| How the shift from one high-energy pass to multiple low-energy passes came about | The dose-response relationship between total energy and outcome |
| “900 shots” is 86.3% agreement in a survey of 82 doctors | A trial putting 900 shots against 600 |
| Second-degree burns 0.36% per shot under the old method | The slope of increase between shot count and adverse events |
| With a different tip the same shot count is a different amount | A prior paper addressing this incomparability — we did not find one |
Evidence that a bigger number on the price list makes the treatment better does not exist at present. Nor is there evidence that a smaller one is insufficient. This is an area where custom has run far ahead of the data, and we think it is better to compare knowing that.
Frequently asked questions
Is there really no difference between 300 and 600 shots?
It does not mean there is no difference; it means there is no material comparing them. We did not find a study in humans that randomly assigned different shot counts. Covering a wider area plainly needs more shots, but there is no evidence that “twice the shots on the same area makes it twice as good”.
I have been told I need 900 shots.
The source of that number is a 2017 Korean survey of 82 doctors in which 86.3% agreed that “900 shots is appropriate for the face in the 35–65 age range”. It is a tally of expert opinion, not a comparative trial. A value worth noting, but hard to use as grounds for “you need it”.
Is the shot count not something the doctor decides?
How much to use is decided, but the total pulse count is sealed into the tip in advance. The US medical device registry records it as a specification too, as “0.25 cm², 450 REP” and “4.0 cm², 600 REP”. So “how many shots” is in practice closer to how many tips are used.
Do more shots hurt more, or carry more risk?
There is no study analysing the relationship between shot count and adverse events. Second-degree burns of 0.36% per shot were reported under the old high-energy method, while conversely recent low-energy multiple-pass studies report zero adverse events even at 600 shots. What sets the risk appears to be the intensity of each delivery and the way shots are overlapped rather than the count.
How should I check the amount of treatment, then?
The three most practical are which tip, where on the face, and over how many passes. The same 600 shots over the whole face and over the jawline alone are entirely different densities. A shot count given without naming the tip is a number that cannot be compared between clinics.
Why is it now gentle over several passes?
The method changed in the mid-2000s. The evidence was a histology study in three people and a survey of 14 physicians, and in that survey the “too painful” response was reported to have fallen from 45% to 5%. The point was not to raise the total but to lower the intensity of each delivery.
How many shots does the manufacturer recommend?
The manual we checked carries no recommended shot count for the face. What it sets instead is the endpoint, “until the patient reports heat feedback of 2.0–2.5 on a scale of 0 to 4”. The “100–2000” that appears in the manual sits in a passage explaining cryogen consumption and is not a clinical recommendation.
Is XERF counted in shots too?
XERF also has a maximum shot count set per tip (i05 400 · i10 300 · E40 600 · E60 600). But everything written above applies unchanged — with a different tip the same number is a different amount, and there is no study comparing shot counts for XERF. The state of the material on XERF overall is set out in how far the evidence has come.
Which is better, doing a lot in one go or splitting it up?
We did not find material comparing them. There is a piece in which one author wrote that “300 shots twice may be better than one high-energy session”, but no citation is attached to that sentence and it was a technique note carrying only two cases. It is hard to use as evidence.
Is this piece saying shot count is meaningless in the end?
No. Covering a wide area evenly does take that many shots — that is a matter of area. What we say has no evidence behind it is the other claim, “putting more shots into the same area makes the result proportionally better”. Hear the two apart and you have it.
Who wrote this
Written and reviewed by Lee Chi-Hak, MD, medical director of Miso Clinic in Daegu, South Korea. Every study cited above is given together with its design, its size and the limitations the authors themselves recorded, and where we could not find data, we have said that we could not find any.
| Medical director | Lee Chi-Hak, MD |
|---|---|
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References
- The shot as a specification sealed into the tip — registration entries in the US FDA Global Unique Device Identification Database (GUDID).
TT0.25F6-450= “FLX TREATMENT TIP, EYE, 0.25CM2, 450 REP”,TT4.00F6-600= “FLX TREATMENT TIP, TOTAL, 4.0CM2, 600 REP”. The market's price units of 300 · 600 · 900 fall out as multiples and combinations of these specifications. The maximum shots per XERF tip (i05 400 · i10 300 · E40 600 · E60 600) are the manufacturer's published specification. - The manufacturer's endpoint criterion — Thermage CPT System Technical User’s Manual, Solta Medical, Model TG-2B-P, document number NP009240-06, September 2021 (confirmed by search · extraction within the document). p.49 — “Continue to treat, adjusting the Treatment Level setting up or down within the recommended range of Treatment Level settings, until the patient reports heat feedback of 2.0–2.5 on a scale of 0 to 4”. p.30 — “The number of REPs delivered varies widely (100-2000) based on the size and cooling profile of the Treatment Tip in use.” That sentence sits in the section explaining cryogen canister consumption — it is not a clinical recommendation. No recommended total REP count for the face · body was found in the manual.
- The protocol shift — Fitzpatrick R, Geronemus R, Goldberg D et al. Multicenter study of noninvasive radiofrequency for periorbital tissue tightening. Lasers in Surgery and Medicine 2003;33(4):232–242, PMID 14571447 (abstract confirmed) — 86 subjects, a single session, 83.2% improvement in periorbital wrinkles, second-degree burns 0.36% (21 events in 5,858 deliveries), residual scarring in 3 subjects at six months. / Kist D, Burns AJ, Sanner R et al. Ultrastructural evaluation of multiple pass low energy versus single pass high energy radio-frequency treatment. Lasers in Surgery and Medicine 2006;38(2):150–154, PMID 16493679 (abstract confirmed) — three subjects, 1.5 cm², single high energy versus 3–5 low-energy passes, transmission electron microscopy. / Dover JS, Zelickson B; 14-Physician Multispecialty Consensus Panel. Results of a survey of 5,700 patient monopolar radiofrequency facial skin tightening treatments. Dermatologic Surgery 2007;33(8):900–907, PMID 17661932 (abstract text confirmed) — old algorithm “too painful” 45% · tightening at six months 54%, new algorithm 5% · 92%. Not a randomised trial but a survey of 14 physicians. / Bogle MA, Ubelhoer N, Weiss RA et al. Lasers in Surgery and Medicine 2007;39(3):210–217, PMID 17304562 (abstract confirmed) — 66 subjects, up to 5 passes, a mean of 556 shots, a mean of 83 J/cm², 92% improved at six months, though the instrument-measured objective indices declined over time. This paper's shot-count stratified analysis is cited in secondary literature as a band of 76–368, which does not match the mean of 556 in the abstract, so without having confirmed the full text we have not used this material as evidence in the body of this piece.
- The only dose-response experiment with shot count as the variable (animal) — Roh H, Lee YI, Jung J et al. Innovative Facial Contouring Using a Monopolar Radiofrequency Device with Continuous Water Cooling: An Integrated Clinical and Preclinical Study. International Journal of Molecular Sciences 2026;27(12):5162 (full text confirmed). This paper carries both a single-arm clinical study in 22 people and a preclinical study in pigs, and the figures below are the porcine part (it is the same paper as the 22-person human part cited in monopolar and bipolar). Nine pigs in vivo, 4 cm² tip, level 2.5 (16.25 J/cm²), 1 · 6 · 12 shots on the same site, histology at 2 · 4 · 8 weeks. Collagen fibre density increased most and earliest in the 12-shot group (p<0.05). Limits — not human, and not “how many shots over the whole face” but “how many times overlapped on one point”, and since 12 shots was the highest dose group the saturation point is unknown.
- The source of “900 shots” — Suh DH, Hong ES, Kim HJ et al. A survey on monopolar radiofrequency treatment. Dermatologic Therapy 2017;30(5):e12536, PMID 28805286 (abstract confirmed) — 82 survey responses analysed, 86.3% agreeing that “900 shots is appropriate for facial tightening in the 35–65 age range”. The follow-up — same authors, Dermatologic Therapy 2020;33(6):e14284, PMID 32902088 (confirmed in summary form only) — 52 respondents, a preference for the 600 REP 4 cm² tip. Both are surveys, not comparative trials.
- The professional consensus — Chapas A, Biesman BS, Chan HHL et al. Consensus Recommendations for 4th Generation Non-Microneedling Monopolar Radiofrequency for Skin Tightening: A Delphi Consensus Panel. Journal of Drugs in Dermatology 2020;19(1):20–26, DOI 10.36849/JDD.2020.4807. A panel of 8 · three rounds · 19 recommendations. The abstract states “device specific guidelines to help guide clinicians to achieve the best outcomes are lacking”. The full text is paywalled, so we were not able to confirm whether the 19 recommendations include an item on shot count.
- Adverse events — de Felipe I et al. Journal of Cosmetic Dermatology 2007;6(3):163–166, PMID 17760693 (abstract confirmed) — 290 patients · second-degree burns 2.7% across 757 treatments, persistent erythema 1.22%, sessions in which pain was severe 11.49%, plus headache · scarring · oedema · fat atrophy · facial nerve palsy. Mean dose 81 J/cm², a 1 cm² tip · 2.3-second pulses. Note — this 2.7% is the rate of “second-degree burns” as given in the primary paper. Some reviews carry the same number across as “all adverse events”, so in secondary citations the index may have been changed. The authors attributed their high burn rate to the way shots were overlapped and recommended “do not stack a shot immediately on the spot just treated” (this sentence is partly corrupted in the reconstructed abstract, so we have conveyed the sense only). / Shin J et al., Cosmetics 2024;11(3):71 (full text confirmed) — 600 shots · 36.60 ± 2.46 kJ in total, mean pain 0.4/10, zero burns · scarring. / Wanitphakdeedecha R et al., Dermatology and Therapy 2022;12:2563–2573, DOI 10.1007/s13555-022-00817-8 (full text confirmed) — 412 ± 49 shots · 31 ± 4.7 kJ, immediate erythema 83.3% (resolving within 1–2 days), zero complications at 3 · 6 months. / Narins RS et al., Dermatologic Surgery 2006, PMID 16393612 — a paper on contour abnormality and fat atrophy from over-treatment. Its title is rare, preventable, and correctable. The reported incidence is 0.14% against estimated procedures from August 2002 to August 2004, falling below 0.04% after an operator training programme was introduced in 2004. That is, this complication was reported to depend on over-delivery and operator skill rather than on the shot count itself.
- Area correction · measured dose — Yang YS et al., Journal of Clinical and Aesthetic Dermatology 2024;17(2):20–22 (full text confirmed, 3 versus 4 cm² split-face, 300 shots each, 16.4 versus 16.6 J/cm²) / Suh DH et al., Lasers in Medical Science 2025;40:530, DOI 10.1007/s10103-025-04788-y (full text confirmed, 0.25 cm² eye tip, 225 shots per eyelid · 450 for both eyes, 7–10 passes per eye, no adverse events). The nominal treated area is a value we calculated as tip area × shot count and is not written that way in any of the papers — in practice there is 15–30% overlap. We did not find any literature addressing head on the point that “a shot count is incomparable unless the tip is stated”.
- What we did not use as evidence — the technique note containing the statement that “300 shots twice is better than one high-energy session” (Journal of Cosmetic Medicine 2025;9(1):48–51) was not used as evidence in the body because it presents only two cases, has no control group · statistical analysis, and attaches no citation to that sentence. The total energy figures in Yang 2024 were not cited because the text carries a unit error, with
16-19kJ/cm²and16.4 J/cm²both written. The “300 versus 600 versus 900 shots” comparisons in Korean clinic advertising · blogs are examples of the existence of a custom, not medical evidence. - What we were not able to confirm — (1) a study in humans randomly assigning and comparing shot counts — we were not able to confirm that one exists (2) the dose-response relationship between total energy and outcome (3) the slope of increase between shot count and adverse events (4) the full text of the shot-count stratified analysis in the 2007 observational study (5) the full text of the 19 recommendations in the 2020 Delphi consensus (6) what happens beyond 12 shots in the pig experiment.
- Continuing pieces — the four EFFECTOR tips, what changes when the tip changes, how far the evidence for XERF has come, aftercare following RF treatment, monopolar and bipolar.
Everything in this column is general information and does not replace medical diagnosis or treatment. Effects and side effects vary with individual skin condition, age and underlying illness, and the same result is not guaranteed for everyone. Any decision to proceed should be made in an in-person consultation with a physician.
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