Herbal THRs versus food supplements, reviewed on what the registration proves

This desk spends most of its time explaining that a supplement is not MHRA-approved and not licensed, and that anybody implying otherwise is reaching past the law. One corner of the shelf is the exception: the carton really does carry a number from the Medicines and Healthcare products Regulatory Agency. That is the traditional herbal registration, or THR — publicly listed, and on this desk’s reading the most misread mark in the aisle, because what it certifies is not what buyers assume.

The two categories, side by side

Two legal statuses, one plant

Registered herbal medicine	A medicinal product registered by the MHRA and carrying a THR number
Herbal food supplement	A food under GB food law — not a medicine, and holding no MHRA registration
What a THR file must show	Quality, safety and at least 30 years of traditional use, per MHRA guidance
What it need not show	Efficacy — the scheme rests on traditional use, and says so
Wording on the box	A THR names a minor complaint from MHRA's permitted indications list; a supplement may use authorised register claims plus botanical claims still 'on hold'
Where to check	MHRA's public list of granted THRs — page updated 28 October 2025, PDF dated 27 October — carrying 155 numbers

What the MHRA actually asks for

The agency’s guidance on applying for a THR is unusually legible for a regulatory page, and its shape is the story. Registration is granted only where the medicine treats minor conditions not requiring medical supervision — the example given is a cold. A major condition needs a marketing authorisation instead.

The file runs to a technical dossier on ingredient quality, an expert safety review signed by a doctor, pharmacist, qualified scientist or professional-body herbalist, a draft summary of product characteristics, and mock-ups of the label and leaflet. The intended use must appear on MHRA’s permitted indications list, and the applicant must evidence 30 years of traditional use for the stated condition, 15 of them in the EU or EEA for products marketed UK-wide or in Northern Ireland. Assessment usually takes 210 days. That is a higher bar than a herbal food supplement clears.

What it does not prove

The register discloses its own limit, in the heading of its indication column: each entry is a traditional herbal medicinal product used for something, “based on traditional use only”. Efficacy evidence forms no part of the dossier. The THR Certification Mark, which the guidance says shows a product meets the required standards of quality, safety and evidence of traditional use, does that work and not a millimetre more.

The same plant, two shelves

Valerian sits on both sides of the line.

On the medicines side, MHRA’s list of granted registrations records Kalms Night under THR 01074/0229, held by G R Lane Health Products Limited, each tablet stated as 96mg of extract from valerian root, equivalent to 384 to 480mg of the root, indicated for the temporary relief of sleep disturbances. Those figures are quoted from the register as published, not from a pack.

On the food side the wording comes from a different list. The Great Britain nutrition and health claims register — the Department of Health and Social Care’s roll of authorised and rejected wordings, last updated 19 May 2026 — carries no entry for valerian at all. That absence is not silence. The wording sits instead on the department’s parallel list of Article 13(1) claims held “on hold”, where entry 4222 records “helps to maintain a natural sleep” against Valeriana officinalis; the compliance guidance says such claims may be used, in line with a 2014 bulletin, until a decision follows the call for evidence. So the food carton may speak — but from a list parked before anyone finished assessing it, on wording the trader itself must substantiate.

The asymmetry decides the purchase. A herbal food supplement is governed as food rather than as a medicine, and makes no offer to diagnose, treat, cure or prevent a thing. The registered product sits inside the medicines regime and may name the complaint it is for. Neither status settles whether the plant works.

Where the supplement still has a case

The registered route is slow, costly and narrow: 155 numbers is not many, and for most herbs the real choice is between a food supplement and nothing. Nor is food law an absence of law: the on-hold list’s own preamble warns that wordings construed as medicinal must not be made on foods, and sends traders to the MHRA on borderline products and to the Food Standards Agency on possible unauthorised novel substances. The supplement shelf sat outside the medicines framework when the MHRA drew its microbiome line; outside it is not outside the law.

Pros and cons

The honest ledger on a registered product

Pros

The number on the box is checkable against a public MHRA list
Quantitative composition is published on the list, so strength is verifiable off the pack
A patient information leaflet is required in the file, and the register says to read it
The indication comes from MHRA's permitted list, so the front of the box is bounded

Cons

Registration rests on traditional use; efficacy evidence is not required, and the register says so in its column heading
The certification mark invites reading as proof the product works, which is not what it certifies
The register warns on page one that not all listed products may be marketed, so a number on an old carton verifies nothing by itself
Herbal actives can interact with prescribed medicines, and a registration number changes nothing there
MHRA charges for the route — from £2,950 to apply on the standard scale, plus £92 a year to hold it, per the agency's 2025-27 schedule — and that buys paperwork, not potency
The wording advantage is narrower than it looks: a botanical supplement may still carry an 'on hold' claim

Verdict

What you buy is an assessed dossier, a published composition, a leaflet and an indication justified against a documented 30-year history. What you do not buy is proof of effect, and the scheme never offered it: read the mark as a statement about the factory and the archive, not the outcome.

On whether a herb is safe alongside a prescription, the register says check the leaflet; a pharmacist is the better first call.