NWPharmaTech CHR-P Research Programme

Science · Understanding cannabinoids

Cannabis, cannabinoids and medicines: understanding the difference

The word cannabis can refer to a plant, a preparation made from it, or products with very different compositions. Cannabinoids are compounds discussed within this field. Two of the best known are cannabidiol, usually called CBD, and delta-9-tetrahydrocannabinol, usually called THC.

Start with four distinctions

The organising question is: which compound, in which product, studied in which people, for which outcome? Sources: Englund et al. 2023, NHS England: CBPMs

  1. Cannabis

    The plant and, in everyday usage, preparations made from it. Their composition varies widely.

    Ask: Which plant material or preparation?

  2. Cannabinoid

    A compound in this area of pharmacology, such as CBD or THC. The compounds do not all have the same effects.

    Ask: Which compound, at what dose?

  3. Formulation

    The way ingredients are prepared and delivered, such as an oral solution, spray or capsule.

    Ask: Which formulation and route?

  4. Medicine and evidence

    A product used within a medicinal framework. Its specific approval status and evidence still need to be identified.

    Ask: Which product, in whom, for which outcome?

Four separate questions. Each step needs its own evidence: a plant does not become a proven medicine automatically, and a finding for one compound or product does not transfer to another.

A signalling system already present in the body

Two long translucent membrane shapes face each other across a narrow gap holding two small signalling-molecule forms, in a bright room.
Conceptual illustration of signalling between cells. It is not a molecular model and does not show where any compound binds or what it does.

The body produces signalling molecules called endocannabinoids, including anandamide and 2-AG. The endocannabinoid system includes these molecules, receptors such as CB1 and CB2, and enzymes involved in making and breaking down the signals. Sources: Health Canada 2018

In cell experiments, THC and 2-AG both activated CB1 signalling, and CBD reduced that signalling. Sources: Laprairie et al. 2015 A laboratory mechanism is a reason to investigate, not evidence that adding a cannabinoid will improve health or correct a deficiency.

Different compounds, different actions

In experiments in people, THC impaired memory and produced temporary psychotic symptoms such as paranoia. Sources: Englund et al. 2013, Englund et al. 2023

CBD does not produce the THC-like high. Sources: Health Canada: about cannabis Non-intoxicating does not mean inactive or risk-free. Sources: Health Canada: CBD For example, the UK product information for one CBD medicine lists sleepiness among its side effects. Sources: Epidyolex SmPC

CBD is being investigated for several possible medical applications. Whether it helps depends on the product, the population and the outcome being studied. A possible mechanism is a reason to investigate a treatment, not proof of clinical benefit. Sources: McGuire et al. 2018, Boggs et al. 2018

Other cannabinoid names, including CBG, CBN and THCV, may appear in research or product descriptions. Each requires its own evidence assessment; CBD or THC findings cannot be assigned to another molecule. This introductory page makes no treatment claims for these compounds.

CBD and THC: different effects, complex interactions

Why formulation and route matter

Swallowing a compound and inhaling it are different exposures. Food, accompanying ingredients and other medicines can also change how a compound is handled. A concentration printed on a label does not by itself tell us how much reaches the bloodstream, the brain or a relevant biological target.

For example, CBD dissolves poorly in water. Taken by mouth on an empty stomach, only about 6% of a dose is estimated to reach the bloodstream, and a high-fat meal increases absorption several-fold. Sources: Perucca and Bialer 2020, Taylor et al. 2018 CBD can also change how some other medicines are handled; the UK product information for one CBD medicine describes an interaction with clobazam. Sources: Epidyolex SmPC

For NWPharmaTech’s formulation research, see the formulation explainer. It distinguishes what the formulation is designed to do from what has been measured.

From cannabis to medicines: why products are not interchangeable

Our programme. NWPT-SM32300 is investigational. General cannabinoid research does not establish that it is effective. The Programme Room explains what has been studied, what is planned and what remains unknown; the NWPT formulation section explains what the formulation is designed to do and what has been measured.