Polynucleotide and regenerative injectable glossary

This glossary explains common terms used around polynucleotide and regenerative injectables in plain language. It separates molecular descriptions, treatment shorthand and UK regulatory language, because these do different jobs. Where a term lacks a settled definition or a product-specific legal status, that uncertainty is stated rather than filled with assumption.

How to use this glossary

Words used on a treatment page can describe a molecule, a manufacturing category, a proposed treatment effect, a legal status or a step in a consultation. They should not be treated as interchangeable. In particular, a scientific description of an ingredient does not establish what a finished product is authorised, intended or suitable to do.

Polynucleotide is a molecular term from biochemistry. Medical device, medicine and prescription-only medicine are regulatory terms whose application depends on the individual product and its intended purpose. Biostimulation, course and regenerative are commonly used treatment terms, but they do not by themselves specify a clinical outcome, a legal classification or a standardised protocol.

A reader can use the definitions below to ask more precise questions. For example, asking whether a product is a medical device or medicine is different from asking what it contains. Asking what evidence supports a proposed effect is different again from asking who will prescribe or inject it. The Medicines and Healthcare products Regulatory Agency, usually called the MHRA, is the UK body associated with the regulation of medicines and medical devices.

This is a language reference, not an assessment of any named product, practitioner or treatment plan. A label, instructions for use, prescription record and consent record may contain the information needed to resolve a term in a particular case. Where those documents are unavailable, a broad term on a webpage may not answer the question a patient actually needs to ask.

Molecules and material terms

Polynucleotide

In biochemistry, a polynucleotide is a chain of nucleotide units. DNA and RNA are familiar biological examples. In injectable marketing, the term may describe material made up of nucleotide chains, but it is not, on its own, a settled definition of a particular finished injectable product. The molecular meaning comes from biochemistry; the status and intended use of a product require product-specific information.

PDRN

PDRN is commonly used as an abbreviation for polydeoxyribonucleotide or polymerised deoxyribonucleotide material in biomedical literature. Usage is not fully uniform across clinical marketing, scientific papers and product literature. It should therefore not be assumed that every product described with PDRN has the same chain length, concentration, source, processing method or regulatory status. This is a terminology issue arising from molecular biology and product documentation, rather than a universal clinical definition.

Polynucleotide product

A polynucleotide product is a practical shorthand for a finished product presented as containing polynucleotide material. It is not a legal classification. The relevant questions are the product's intended purpose, route of administration, instructions for use, ingredients, sterilisation information and regulatory documentation. The MHRA's framework distinguishes the regulation of a finished medical product from a loose description of an ingredient.

Platelet-rich plasma

Platelet-rich plasma, often shortened to PRP, refers to plasma prepared from blood with a higher platelet concentration than the person's baseline blood sample. The exact preparation can differ according to collection, processing and use. This definition comes from haematology and transfusion-related laboratory practice. PRP is not another name for a polynucleotide product, even where both are discussed under the broad marketing label of regenerative treatment.

Exosome preparations

Exosome preparations is a term used in cell and extracellular-vesicle science for preparations said to contain exosomes or related extracellular vesicles. It is not a synonym for polynucleotides or PDRN. Questions about vesicles, their manufacture and their clinical implications need separate assessment and are outside this polynucleotide glossary.

Effect and treatment-plan language

Biostimulation

Biostimulation is commonly used to suggest that an intervention may prompt a biological response in tissue. It is not a settled regulatory definition, nor does it state what response will occur in an individual. The word may refer to a proposed mechanism, laboratory observation or intended longer-term effect. It should not be read as a guarantee of visible change. The distinction between mechanism and clinical outcome is a basic principle of evidence appraisal.

Volumising

Volumising describes an intended physical increase in volume, usually by the presence and placement of a material. In aesthetic practice, hyaluronic acid filler is generally discussed in relation to volume, shape or contour. The term does not establish that every hyaluronic acid product has the same indication, longevity or risk profile. Product instructions and anatomical assessment remain relevant.

Polynucleotide product and hyaluronic acid filler

A polynucleotide product and a hyaluronic acid filler are different material categories. Hyaluronic acid is a polysaccharide, whereas polynucleotides are chains of nucleotide units. A filler may be intended to provide volume through its physical presence. A polynucleotide product may instead be described using proposed biological-response language. These descriptions do not settle either product's individual regulatory status, evidence base or suitability. The chemical distinction comes from biochemistry; intended purpose comes from the manufacturer's product documentation.

Course

A course means a planned series of appointments. There is no universal clinical definition stating how many appointments it contains, how far apart they are or what result should follow. A plan should identify its stated objective, the reason for the proposed timing, what will be recorded and what would lead to review or a decision not to continue. This is treatment-planning language, not a standard established by the word itself.

Review appointment

A review appointment is a later assessment of the treatment area, response, adverse effects and next steps. It is distinct from an automatic further procedure. Good decision-making practice requires that the person can ask questions and revise a decision as circumstances change. The General Medical Council's guidance on decision making and consent supports discussion that is tailored to the individual and continues through care.

Product status, devices and conformity markings

Medical device

A medical device is a regulated product category. Under the UK medical-device framework described by the MHRA, a device's intended purpose and its principal mode of action matter to classification. A statement that an injectable is a device should be capable of being supported by its product documentation. It does not mean that the product is risk-free, clinically proven for every promotional claim or appropriate for every person.

Medicine

A medicine is a different regulated category. The MHRA explains that medicines are regulated separately from medical devices. In broad terms, the distinction can involve presentation, intended use and mode of action, but borderline questions are product-specific. A webpage should not resolve that question merely by calling a product regenerative, injectable or medical grade.

UKCA marking and CE marking

UKCA marking and CE marking are conformity markings associated with regulated products, including medical devices in relevant circumstances. The MHRA publishes the Great Britain framework for medical-device conformity marking and also sets out continuing recognition arrangements for CE-marked devices. The applicable route can depend on the device type, certification and timing. A marking is not a general endorsement of every marketing statement, nor does it establish that a product is licensed as a medicine.

Prescription-only medicine

A prescription-only medicine, often called a POM, is a medicine subject to prescription controls. The MHRA's medicines framework uses legal supply categories, including prescription-only status. Whether a particular injectable is a POM cannot safely be inferred from the fact that it is injected, offered in a clinic or described as professional-use. The finished product's legal classification and supply route are the relevant facts.

Screenshot rule: a conformity marking answers a conformity question within a regulatory framework. It does not answer the separate questions of who may prescribe, who may administer, what has been consented to or what outcome evidence exists.

Prescribing, injecting and remote care

Prescribing

Prescribing is the clinical and legal process by which an authorised prescriber issues a prescription for a medicine. It is relevant only where the product is a medicine requiring prescription. The General Medical Council sets professional standards for doctors who prescribe, and other professions have their own applicable standards and scopes of practice. The product classification must be established before the term is used as an explanation for an injectable pathway.

Remote prescribing

Remote prescribing means prescribing without the prescriber and patient being in the same physical location at that point in the process. It is not a separate product category. The General Medical Council's prescribing guidance addresses the need for sufficient information to make a safe prescribing decision and applies whether contact is remote or in person. The method of assessment, identity checks, medical history, examination where needed, record keeping and follow-up arrangements may all matter.

Injector

Injector is a practical description of the person administering an injectable. It is not a protected professional title. A reader should instead identify the person's profession, registration where applicable, training, indemnity arrangements and role in the clinical pathway. The General Medical Council, Nursing and Midwifery Council, General Pharmaceutical Council and Health and Care Professions Council each maintain registers for professions they regulate. Registration does not, by itself, answer every question about competence for a particular procedure.

Delegation

Delegation means allocating a task to another person while retaining the responsibilities set by the relevant professional standards and workplace arrangements. It should not obscure who assessed the patient, who made any prescribing decision, who administered the injection and who is responsible for follow-up. The record should make these roles clear.

The legal and professional position can differ across the four UK nations and can change. This glossary therefore defines the language rather than offering a substitute for current nation-specific legal advice.

Consent, cooling-off language and allergy testing

Consent

Consent is a person's voluntary and informed agreement to a proposed intervention. It is a process, not simply a signature on a form. The General Medical Council's decision-making and consent guidance describes the need to give patients relevant information, support them to make decisions and record the discussion appropriately. For an elective injectable, relevant discussion may include uncertainty, alternatives, material risks, the identity and role of those involved, likely follow-up and what to do if a problem occurs.

Cooling off

Cooling off is often used to mean time between a consultation and a procedure so that a person can consider their decision. There is no single universal clinical cooling-off period created by this phrase for all injectable procedures. It should not be presented as proof that consent is valid. The key question is whether the person has adequate time and information, is free to decide, and can ask further questions. Consumer-law cancellation rights and professional consent standards are separate subjects.

Patch testing

Patch testing is a diagnostic method used in dermatology to investigate delayed contact allergy, usually by applying substances to the skin under controlled conditions. It is not a general test that proves an injectable will be safe. A negative patch test does not exclude all allergic, inflammatory or injection-related reactions, particularly where the route of exposure differs. The meaning of patch testing comes from dermatology and allergy practice; whether testing is appropriate depends on the material and clinical history.

Allergy history

An allergy history records prior reactions, suspected triggers, timing and severity. It is different from a confirmed allergy diagnosis. Where a past reaction is significant or unclear, clinical assessment may be needed before any elective intervention. A marketing statement about a product's source should not replace that assessment.

Registers, reporting and complaint routes

A register is an official list maintained by a regulator or statutory body. It can help establish whether a named professional is registered in the profession they claim. It does not certify every treatment offered, verify every advertisement or determine whether a particular intervention was appropriate.

A complaint is a concern raised with the provider or another relevant body about service, conduct, communication or care. The appropriate route depends on what happened and who provided the service. Keep contemporaneous records, including consent material, appointment dates, product details if held, photographs where relevant and the wording of any response. A suspected adverse reaction can be both a care concern and a potential Yellow Card report. Those routes have different purposes.

Limits of this reference

This glossary does not decide whether any individual should have an injectable, whether a particular anatomical area is appropriate, or whether a claimed result is likely. It does not interpret laboratory evidence as proof of patient benefit. It also does not assess exosome preparations beyond distinguishing the term from polynucleotides, because vesicle science requires its own reference framework.

It does not provide legal advice, determine the classification of a named product, or state who may lawfully perform every procedure in every UK nation. Product classification, professional scope, premises rules and enforcement arrangements can depend on current law and specific facts. The MHRA and the relevant professional regulator are more appropriate sources for current product or registration questions.

The definitions apply to readers encountering broad language on webpages, consent forms and treatment records. They may not apply unchanged to hospital care, clinical research, medicines supplied under a particular licence, or products used outside Great Britain. A term can be used accurately in one document and imprecisely in another. Where the intended meaning affects a decision, request the underlying document rather than relying on the label alone.