“How many sessions, and how long does it last?” — sessions and duration by family
After price, this is the question we are asked most. The answer differs by family, but the more important point is that how thick the evidence behind that number is also differs by family. For some products a wide range such as “12 to 30 months” is reported; for others we have decided not to give a figure in months at all. The reasons are set out alongside.
The short answer
Families divide into those we treat as a single session and those we treat as a course. GOURI is one session as the baseline; Rejuran is three to four sessions at three-to-four-week intervals as one course. For duration, Radiesse and DCLASSY are reported longest at 12 to 30 months, and GOURI at about 6 to 12 months. And there are three products for which we give no figure — BYRYZN, because the published research followed patients only to 12 weeks, and Re2O and CellREDM, because the long-term maintenance data is not sufficient. Not inventing a number that does not exist is a principle we hold to.
Why there is no single answer
There are three reasons “how many months does it last?” is hard to answer in one sentence.
First, what counts as “lasting” is not fixed. How long the material remains in the body, how long a visible change remains, and how long the person remains satisfied are three different things. Studies measure different ones, so the numbers scatter.
Second, the point at which a study stopped observing is routinely read as the duration. A study that followed patients to 12 weeks says “it was maintained to 12 weeks”; it says neither “it only lasts 12 weeks” nor “it lasts beyond 12 weeks”. In advertising this readily turns into “lasts three months”.
Third, individual variation is often greater than the difference between products. With age, skin thickness, metabolic rate and lifestyle in play, the same product behaves differently in the same person from one session to the next.
So in the table below we have put the number and where the number came from side by side. Numbers on their own look comparable, but where the evidence differs in thickness they cannot be set against each other.
Sessions and duration by family
| Product | Sessions and intervals | Duration | Where the number comes from |
|---|---|---|---|
| GOURI liquid PCL |
One session as the baseline 1–2 more at 4–6 week intervals if needed |
About 6–12 months | Based on the period over which PCL degrades in the body. Where greater improvement is wanted we sometimes advise a programme of three sessions at four-week intervals |
| Rejuran PN |
3–4 sessions at 3–4 week intervals (one course) |
Up to 12 months reported in some studies | The evidence is not thick and individual variation is wide. We treat it as a course rather than judging after one session because the change is hard to feel after the first |
| Radiesse · DCLASSY CaHA |
According to condition and area | 12–30 months (wide reported range) |
Based on the microspheres degrading over one to two years, and the variation between studies is wide. Among the boosters this is on the longer side |
| BYRYZN cross-linked HA |
Studied as 3 sessions at 2-week intervals | We give no figure in months | What the published research confirms is up to 12 weeks. With no data over a longer period we do not use the phrase “lasts so many months” |
| Re2O · CellREDM hADM |
Decided from condition and goal | We give no figure in months | Published data on long-term maintenance is not yet sufficient. We review the course after one session and decide together whether to add more |
The three lifting devices (XERF · Density · Oligio Kiss) are not in the table. Because for all three we could not verify any published clinical trial of the device itself, we have no basis on which to put sessions or duration into figures. The principle of not transcribing class-level research as if it were evidence for a specific device applies here too.
What “6 to 12 months” actually means
Faced with a range like that, most people read it as “so which am I?”, and read that way it leads either to disappointment or to false confidence. Here is what the range means.
- It is an average, not a promise. It means there are people at six months and people at twelve, and there are people outside that too
- It does not end one day all at once. The material degrades gradually, so the change fades gradually. It is less “at month six I was back to where I started” and more “at some point it became similar to before”
- How long the material remains and how long it shows are different. The 12 to 30 months for CaHA is based mainly on the degradation period of the microspheres; it does not mean the visible change stays the same size throughout
- There is no guarantee the second treatment will be like the first. The skin has already changed, and when the starting point differs so does what you feel
Repeat treatment is set by condition, not by the calendar
We do not work to “it has been six months, so it is time”. We look at the following together and decide.
- We go back to why you had it done. If texture was the concern, we look at texture; if density was, we look at density. We measure where you are now against the original goal
- The point at which the change starts to fade is usually when to discuss the next one. Better than waiting for a complete return to baseline and starting again
- We look at the season and your diary. Treatments that may leave a bruise do not go in front of something important
- We also consider whether to repeat the same product or change it. If what the first course resolved and what it left behind are different, a different family suited to what remains may be better
- Deciding not to treat is included. If the current state is fine, we do not recommend treating to fit the calendar
What affects how long it lasts
These are the reasons the same product goes differently in different people. Most are hard to change; a few can be.
| Factor | How it works |
|---|---|
| Age and skin thickness | The thinner the dermis and the lower its regenerative capacity, the smaller the response to the same stimulus tends to be |
| Metabolism and activity | These treatments use materials that degrade, so a faster metabolism tends to mean a relatively shorter run |
| Ultraviolet light | The single largest external driver of skin ageing. Of the things you can change, this has the greatest effect |
| Smoking | Known to affect blood flow and collagen metabolism |
| Weight change | When facial fat volume changes, the impression of volume changes with it. It can feel as though the treatment has worn off |
| Area | Areas that move a great deal, around the mouth for instance, tend to run relatively shorter |
| The volume and plane placed initially | Less than the appropriate volume feels shorter. That does not make placing more the answer — particularly with families that cannot be reversed |
Sun protection can matter more than which product you choose. This is something we say often to people who spend a long time deciding between boosters. Ultraviolet light is what erodes a treated result fastest, and protecting against it costs almost nothing while the direction of the effect is clear.
When treatments are combined
Having several treatments together is common. These are less cases of combinations that cannot be done than cases where order and interval matter.
- Injections and heat-based devices on the same day depends on the area and the product. Applying heat to material already placed can be a problem in some sequences, so we usually plan them in separate steps
- Placing several families into the same area at once is not something we recommend. If a problem arises there is no way to work out what caused it
- Families that cannot be reversed go later. Establishing the shape first with something reversible and then adding only what is needed is the safer order
- We keep the recovery periods from overlapping. If the swelling and bruising of two treatments coincide, the course becomes hard to judge
Frequently asked questions
How many sessions of a skin booster do I need?
Is one session enough?
How long does the effect last?
Why is there no duration given for some products?
When is the right time for a repeat treatment?
Can I have several treatments on the same day?
What can I do to make the result last longer?
Will the second treatment have the same effect as the first?
Who wrote this
Written and reviewed by Lee Chi-Hak, MD, medical director of Miso Clinic in Daegu, South Korea. The sessions and durations above reproduce what the clinic established product by product while writing the documents in its clinical reference library; where verification was not possible, it says so.
| Medical director | Lee Chi-Hak, MD |
|---|---|
| Address | 4F Bombom Building, 125 Dongdeok-ro, Jung-gu, Daegu, South Korea · Exit 1, Kyungpook National University Hospital Station |
| Phone | +82-53-428-2700 |
| Hours | Weekdays 11:00–19:00 (lunch 13:00–14:00) / Saturday 10:00–16:00 (no lunch break) / Closed Sundays and public holidays |
| Columns | All clinical columns |
| Reference library | All booster and device references |
| Other languages | 한국어 · 日本語 · 简体中文 · Español |
References
- Sessions and intervals (GOURI one session as the baseline · 1–2 more at 4–6 week intervals, Rejuran 3–4 sessions at 3–4 week intervals) are Miso Clinic's clinical practice. They are not product licence terms or society guidelines, and other clinics may work to different figures.
- The 12 to 30 months for Radiesse and DCLASSY is a reported range based on the microspheres degrading over one to two years, and the variation between studies is wide. The 6 to 12 months for GOURI is likewise based on how long PCL takes to degrade in the body.
- The report of up to 12 months for Rejuran rests on evidence that is not thick, with wide individual variation. This is recorded as such in the product reference.
- For BYRYZN, what the published research confirms is up to 12 weeks, so no figure in months is given. That study was an uncontrolled study of 20 subjects, and this limitation is also recorded in the product reference. For Re2O and CellREDM the long-term maintenance data is not sufficient.
- The lifting devices XERF · Density · Oligio Kiss are not included in the sessions and duration table because no published clinical trial of the device itself could be verified.
- The factors affecting duration are a summary of generally recognised tendencies and do not cite studies quantifying the contribution of any individual factor.
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.