Medical cannabis has been legal in the UK since 2018, but confusion around the law is still widespread. Many people are unsure what is legal, what isn’t, and how prescribed medical cannabis fits within UK drug legislation.

This article explains the legal framework surrounding medical cannabis in the UK, including what changed in law, how cannabis-based medicines are regulated and what legal protections apply to patients who are prescribed them.

We don’t provide medical advice or guidance on eligibility here. Instead, this guide focuses purely on the law, helping you understand how medical cannabis became legal and how it is treated under UK regulations today.

When Did Medical Cannabis Become Legal in the UK? 

Medical cannabis became legal in the UK in November 2018, following a change to the Misuse of Drugs Regulations.

Cannabis-based products for medicinal use, officially known as Cannabis-Based Products for Medicinal Use (CBPMs), were moved from Schedule 1 (no recognised medical use) to Schedule 2, allowing them to be prescribed under strict medical supervision.

This change applies only to prescribed medical cannabis. Cannabis remains illegal for recreational use in the UK.

What counts as ‘Medical Cannabis’ under UK Law?

Under UK law, medical cannabis refers specifically to licensed or unlicensed CBPMs that are:

• Prescribed by a specialist doctor
• Supplied by a licensed pharmacy
• Used strictly in line with a valid prescription

These products may include dried flower, oils  or other cannabis-based preparations approved for medicinal use. Products obtained outside of this regulated system are not legal, even if used for symptom relief.

Who is legally allowed to prescribe medical cannabis?

UK law restricts prescribing authority to:

• Doctors listed on the General Medical Council (GMC) specialist register
• Consultant-level clinicians working within authorised clinics

GPs cannot initiate medical cannabis prescriptions, although they may be informed as part of shared care.  This legal structure ensures prescriptions are issued only by clinicians with appropriate expertise and oversight.

How the Private Clinic System Fits into the Law

Most UK medical cannabis prescriptions are issued through private specialist clinics, operating within the legal framework set out by the Home Office and Medicines and Healthcare products Regulatory Agency (MHRA).

From a legal standpoint, this system ensures:

• Prescriptions are clinically authorised
• Products are dispensed by licensed pharmacies
• Patients remain under ongoing medical supervision

The law requires continued follow-up and review as part of lawful treatment.

Legal Responsibilities for Medical Cannabis Patients

Patients prescribed medical cannabis also have legal responsibilities, including:

• Storing medication securely
• Using cannabis only as prescribed
• Vaporizing flower if specified, rather than smoking
• Carrying proof of prescription when in possession of medication

Any changes in symptoms or side effects must be discussed with the prescribing clinic to remain compliant.

Where Perfectly Legal Fits In

Perfectly Legal Vaporizer Supplies does not provide medical advice or treatment recommendations.

Our role is to support prescribed patients by offering:

• Compliant dry herb vaporizers suitable for prescribed use
• Clear, practical information around lawful consumption methods
• Trusted equipment from reputable manufacturers used by patients themselves

For personalised medical guidance or eligibility questions, patients should always speak directly with their prescribing clinic.

Want to Know How to Become a Medical Cannabis Patient?

If you’re interested in how the prescription process works — including eligibility, consultations, and clinics, we’ve created a separate step-by-step guide:

How to Get Medical Cannabis in the UK: A Simple Step-By-Step Guide

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