GMP, GACP and the Pharmacopoeia, explained simply

“Pharmaceutical quality” sounds like a marketing word. In fact, behind it sits a dense web of three Swiss frameworks that touch every medical cannabis flower and every magistral preparation: GACP in the field, GMP in processing, and the pharmacopoeia as the binding yardstick. Anyone who wants to understand the difference from “cleanly grown” has to pass through these three acronyms.

GACP: quality starts in the bed

GACP stands for Good Agricultural and Collection Practice. These guidelines apply to the cultivation and harvest of herbal starting materials, including cannabis flowers intended for medicinal use. Among other things they govern:

selection of genotype and purity of mother plants
soil quality, irrigation and fertilisation
freedom from pesticides and herbicides, or documented application within permitted limits
harvest timing, drying and storage
pest and mould control
traceability of each batch back to the field

Swissmedic, in the cannabis context, explicitly refers to the “Good Agricultural and Collection Practice (GACP) guidelines for herbal starting materials”. GACP is thus the agricultural counterpart to GMP, without which later pharmaceutical processing would not be possible.

GMP: what has to happen after harvest

GMP stands for Good Manufacturing Practice and governs the manufacture of medicines. In Switzerland, both the EU GMP guidelines and PIC/S GMP are binding. Swissmedic verifies compliance through inspections.

Two sections matter most for cannabis:

GMP Part II for pharmaceutical active substances (Active Pharmaceutical Ingredients, API)
GMP Annex 7 for Herbal Medicinal Products

Annex 7 is the actual crux: it sets out at which processing step GMP (no longer just GACP) starts to apply, for example sieving, cutting, extraction or standardisation. Responsibility for correct classification “lies with the companies” (Swissmedic, FAQ).

What GMP specifically requires:

qualified rooms and equipment (cleanroom classes, cross-contamination protection)
trained staff and documented responsibilities
validated manufacturing and testing methods
complete batch documentation
release by a qualified person

In Switzerland, pharmacy compounding (magistral preparation) is also subject to GMP rules: according to the pharmacopoeia and “GMP for small quantities of medicines”.

Pharmacopoeia: the binding yardstick

The pharmacopoeia is the official rulebook that sets out the quality requirements a medicine or an active substance must meet. Swissmedic puts it this way: “A pharmacopoeia is an official rule book. It sets the mandatory quality standards that medicinal products have to fulfil to qualify as safe and effective.”

In Switzerland, two pharmacopoeias apply in parallel:

the European Pharmacopoeia (Ph. Eur.) as the base
the Swiss Pharmacopoeia (Pharmacopoea Helvetica, Ph. Helv.) as a supplement for Swiss-specific items (for example traditional preparations)

Art. 8 TPA requires: “Medicinal products and pharmaceutical excipients placed on the market must meet the requirements of the Pharmacopoeia or of other pharmacopoeias recognised by the Agency, insofar as such requirements are laid down.”

What a monograph regulates

A pharmacopoeia monograph defines, bindingly, for a given active substance or preparation:

identity (e.g. microscopic features, chromatographic fingerprints)
content (e.g. THC and CBD ranges)
purity (heavy metals, pesticides, aflatoxins, microbial load)
test methods by which the above must be demonstrated

Cannabis flowers in the pharmacopoeia

Cannabis flowers have had a turbulent pharmacopoeial history in Switzerland. The Ph. Helv. had, in 2020, been among the first European pharmacopoeias to publish a “Cannabis flos” monograph, because of urgent medical need and the fact that cannabis preparations with THC-CBD ratios outside the authorised active substances had to be available on prescription.

Since 1 July 2024, the Ph. Eur. Cannabis flowers monograph (Supplement 11.5) has been in force. After a transition phase it replaces the prior Swiss monograph, which is “to be repealed shortly” (Swissmedic).

How the three frameworks fit together

Stage	Framework	What it secures
Cultivation and harvest	GACP	Strain purity, pesticide and mould control, traceability
Processing and packaging	GMP (Part II, Annex 7)	Cleanroom classes, validated processes, batch documentation
Specification and testing	Pharmacopoeia (Ph. Eur. / Ph. Helv.)	Identity, content, purity, test methods

Only together do these three layers add up to “pharmaceutical quality”. “Cleanly grown” describes, at best, the GACP layer. What is dispensed in a Swiss pharmacy has additionally passed through the processing and testing layers.

What this means for patients

Every batch of cannabis flowers or cannabis extract from the pharmacy has been tested against a pharmacopoeia specification. There is therefore a measurable, documented standard.
Pesticides, heavy metals and aflatoxins must remain below defined limits; otherwise the batch is not released.
The active-substance content is declared and reproducible. That is the precondition for a therapy to be dosed reliably over weeks.

Anyone trying to understand the difference from black-market products will find it not in vendor marketing, but in these three sober acronyms.

This article summarises Swiss regulation on the pharmaceutical quality of cannabis. It does not replace medical or pharmaceutical advice.

Sources

Swiss Pharmacopoeia (Ph. Helv.), overview · Swissmedic
European Pharmacopoeia Supplement 11.5 (Cannabis flos) · Swissmedic
Good Manufacturing Practice (GMP) approach · Swissmedic
Guidance on GMP compliance of foreign manufacturers · Swissmedic
FAQ on the Cannabis Information Sheet (Annex 7, GACP) · Swissmedic
Ph. Eur. publishes Cannabis flos draft monograph in Pharmeuropa · EDQM, Council of Europe
Therapeutic Products Act (TPA), Art. 8 (requirements for medicines) · Federal Chancellery, Fedlex