What is not known

2.3.1Why publish this at all

Because the alternative is to write around the gaps, and a reference that writes around gaps is a brochure with citations. This category is heavily promoted and thinly evidenced. A reader who arrives here having read a dozen clinic pages will have encountered a great deal of confident language and no acknowledgement that anything is unresolved. Supplying that acknowledgement is the most useful thing this document can do.

It is also the more defensible editorial position. Saying that a question is open is a claim we can support. Saying that a treatment works, or does not, would be a claim we cannot.

2.3.2The central open question

Does anything remain once the material has gone?

Everything commercially significant about this category depends on the answer. If the effect is coextensive with the presence of the material, then the treatment is a hydrating injectable with a course and maintenance schedule, and it should be priced and compared as one. If the effect outlasts the material because the tissue has been changed, then it is a different kind of intervention and the case for a course of it is much stronger.

The study that answers this is not difficult to design. Treat, control, blind the assessment, and measure late. The reason it has not been done at scale is not scientific difficulty.

2.3.3The inventory

About the effect

About safety

About the product

About the market

2.3.4What is known, so that the list above is not misread

An inventory of unknowns can read as a case against a treatment, and it is not intended as one. Several things are reasonably established and should be stated with the same directness.

• The material is fragmented purified nucleic acid, generally fish derived, in a buffered solution. This is not in doubt.
• It binds water, and injecting it into the dermis produces a local physical change. This is not in doubt.
• It is degraded by nucleases and is not expected to persist. This follows from well established biochemistry.
• Most people who have the treatment notice a short term change. Whether that change is biological or physical, and whether it lasts, is what is open.
• The injection procedure itself carries the ordinary risks of injecting into a face, which are known and are described in the safety chapter.

A person who reads both lists and decides to have the treatment has decided something reasonable. A person who reads both lists and decides against it has also decided something reasonable. The purpose of publishing the lists is that the decision should be made with them in view.

2.3.5What would change this page

We will amend this article, and the evidence register that collects its verdicts, when any of the following appear.

• An independent randomised controlled trial with blinded assessment, registered outcomes and follow up past the clearance window.
• A systematic review that finds a body of work capable of supporting a conclusion rather than calling for one.
• Regulatory action, guidance or an assessment from NICE, the MHRA or an equivalent body that bears on the questions above.
• Published ASA rulings that establish what may and may not be claimed for this category in UK advertising.
• Post market surveillance data that gives a genuine denominator for complications.

If you know of something that meets one of those descriptions and is not reflected here, the contact page exists for that purpose, and a correction is not a defeat.

2.3.6How to use this article in a consultation

Not by reciting it. The useful form is a single question, asked without hostility: which parts of this are settled, and which parts are you and I both taking on trust?

A practitioner who separates the two is someone you can have a real conversation with about whether the treatment is right for you. A practitioner who tells you it is all settled has told you something about the quality of information you are going to receive from them for the rest of the relationship, which is more valuable than anything they could have said about receptors.