What is medical cannabis?

Medical cannabis refers to cannabis-based products prescribed by specialist doctors to relieve symptoms of certain health conditions, particularly when other licensed treatments have not worked.

In the UK, these medicines are available only through prescription and must be dispensed by a licensed pharmacy. They are carefully regulated to ensure patient safety and clinical oversight.

Key Characteristics:

  • Prescription-only: Medical cannabis cannot be purchased freely. It must be prescribed by a doctor listed on the General Medical Council’s Specialist Register.
  • For specific conditions: It is usually considered when patients have tried at least two other licensed treatments without success.
  • Forms available: Cannabis-based medicines may be prescribed as oils, dried flowers (for vaporisation), capsules, or sprays.
  • Strictly regulated: All products are controlled by the Medicines and Healthcare products Regulatory Agency (MHRA) to ensure compliance with UK law.

Examples of Authorised Products in the UK

  • Sativex (nabiximols):
    A balanced THC:CBD spray licensed to treat moderate to severe spasticity (muscle stiffness) in multiple sclerosis.
  • Epidyolex (cannabidiol):
    A purified CBD medicine licensed for rare and severe forms of epilepsy, such as Dravet syndrome and Lennox-Gastaut syndrome.

Unlicensed Products

Specialist doctors may prescribe unlicensed cannabis-based products (such as certain oils or dried cannabis flower) if they believe it will benefit an individual patient. These are still regulated under UK law but do not have a specific UK marketing authorisation.

Unlicensed cannabis-based products are prescribed in the UK. Only GMC-registered specialists can prescribe them when standard treatments have failed. While not licensed for UK marketing, they remain regulated to ensure quality and safety.

Key Points

  • Specialist Prescribers: Only doctors on the GMC Specialist Register can prescribe.
  • Unmet Clinical Need: Used only where licensed treatments are unsuitable or ineffective.
  • Named Patient Basis: Prescriptions apply to individual patients.
  • Regulation: Products are unlicensed but regulated for medicinal use.

Definition of a CBPM
A cannabis-based product for medicinal use (CBPM) must:

  • Contain cannabis, cannabis resin, cannabinol, or a cannabinol derivative.
  • Be made for medicinal use in humans.
  • Be regulated as a medicinal product or ingredient.

How the System Works

  1. Referral: A GP may refer a patient to a specialist.
  2. Assessment: The specialist checks if there’s an unmet clinical need.
  3. Team Agreement: A multidisciplinary team supports the decision.
  4. Prescription: If approved, the specialist prescribes the unlicensed medicine.
  5. Monitoring: The specialist tracks progress and adjusts dosage.

Legal Status of Medical Cannabis in the UK

  • Cannabis remains a controlled drug under the Misuse of Drugs Act 1971.
  • Its legitimate use in medicine is allowed under the Misuse of Drugs Regulations 2001, which were amended in 2018.
  • Outside of regulated medical channels, it is illegal to possess, supply, produce, or import cannabis.

What are Cannabinoids?

Cannabis contains over 100 naturally occurring compounds, known as cannabinoids, that interact with the human body in unique ways.

The two most well-known cannabinoids are:

  • THC (Tetrahydrocannabinol): The primary psychoactive compound. In medicine, THC may help with pain, muscle stiffness, and nausea but can also cause drowsiness or dizziness.
  • CBD (Cannabidiol): A non-intoxicating compound. CBD is linked with reducing seizures, easing anxiety, and supporting relaxation, without producing a “high.”
  • Other cannabinoids (CBG, CBC, THCV, etc.): Currently under study for potential therapeutic benefits.

The Endocannabinoid System Explained

The endocannabinoid system (ECS) is a natural network of receptors in the human body that helps regulate:

  • Pain
  • Sleep
  • Mood
  • Appetite
  • Immune response

Cannabinoids in medical cannabis interact with this system, which is why they may help relieve symptoms when other treatments fail.

Medical vs. Recreational Cannabis

It’s important to understand the difference:

  • Medical Cannabis:
    • Prescribed by a GMC specialist doctor
    • Dose and formulation tailored to the patient
    • Regulated for quality and safety
    • Used to relieve specific symptoms or conditions
  • Recreational Cannabis:
    • Illegal to possess or use in the UK
    • Not subject to medical regulation or quality standards
    • Used without medical oversight or prescription

When Might Medical Cannabis Be Considered?

In the UK, medical cannabis is usually considered when:

  • Patients have tried two or more standard treatments without success.
  • Symptoms remain severe or poorly managed.
  • There is supportive clinical evidence (UK or international) that cannabis may help.

Common areas where prescriptions are considered include:

Medical cannabis is not a first-line treatment in the UK. It is a specialist-prescribed option for patients whose symptoms have not improved with standard medicines. With strict regulation, prescription-only access, and emerging evidence, it represents a new chapter in UK healthcare — offering hope where traditional therapies may fall short.