Prescribing CBPMs in the UK: A Practical Guide to the Specialist Pathway

For specialist clinicians, pharmacists and clinic managers: this article sets out the practical regulatory and documentation framework for prescribing cannabis-based products for medicinal use (CBPMs) in the UK. It is written for those already familiar with controlled drug (CD) handling who are considering, or already running, a CBPM service line. It is not clinical advice and it does not promote any product.

What changed in November 2018, and what did not

On 1 November 2018, regulations under the Misuse of Drugs Act 1971 were amended so that products meeting the statutory definition of a cannabis-based product for medicinal use moved from Schedule 1 to Schedule 2 of the Misuse of Drugs Regulations 2001. From that date, suitably qualified specialist doctors gained the legal ability to prescribe unlicensed CBPMs where there is a clear clinical need.

Several things did not change in 2018, and clinicians are often caught out by this:

• Cannabis itself remains a Class B controlled drug under the Misuse of Drugs Act 1971.
• The vast majority of CBPMs available to UK patients are unlicensed medicines — only Epidyolex (cannabidiol), Sativex (nabiximols) and nabilone hold UK marketing authorisations, and only for narrowly defined indications.
• NHS funding routes are restricted; most CBPM prescribing in the UK happens privately.
• All Schedule 2 storage, register and prescription-form rules continue to apply in full.

Who may legally initiate a CBPM prescription

Under the 2018 regulations, only a doctor on the GMC Specialist Register may initiate a prescription for an unlicensed CBPM. General practitioners cannot initiate. They may, in principle, continue a CBPM under a shared-care arrangement, but in practice most GP indemnifiers are cautious about unlicensed-medicine continuation and many GPs decline shared care.

The clinician’s specialty matters. The General Medical Council expects prescribers to work within their scope of competence; a specialist register entry is necessary, but not sufficient. A neurologist prescribing for refractory epilepsy is in scope; the same neurologist prescribing for an unrelated chronic pain indication may not be.

NICE NG144 and where its boundaries sit

NICE published NG144: Cannabis-based medicinal products in November 2019, with a minor update in March 2021. The guideline covers four areas: intractable nausea and vomiting, chronic pain, spasticity, and severe treatment-resistant epilepsy.

The headline positions are narrow:

• Chemotherapy-induced nausea and vomiting: nabilone may be considered as an add-on for adults where conventional licensed antiemetics are inadequate.
• Spasticity in multiple sclerosis: THC:CBD spray (nabiximols) may be considered, initiated and supervised by a clinician with specialist expertise.
• Chronic pain: NICE does not recommend CBD or THC:CBD combinations for chronic pain in adults outside a clinical trial.
• Severe treatment-resistant epilepsy: NICE acknowledges insufficient high-quality evidence to recommend unlicensed CBPMs and signposts the licensed Epidyolex pathway for specific syndromes.

NICE NG144 sets the floor of evidence-based recommendation, not the ceiling of lawful practice. Specialist clinicians may still prescribe unlicensed CBPMs outside NICE-recommended indications where, in their clinical judgement, conventional licensed options have been adequately trialled and the balance of benefit and risk favours treatment — provided the GMC’s standards for good practice in prescribing unlicensed medicines are met.

The British Paediatric Neurology Association (BPNA) and the Royal College of Physicians have issued profession-specific position statements emphasising caution, MDT input, and the use of registries. The Association of British Neurologists has done likewise for adult neurology. These statements are not legally binding but are the reference points clinicians will be measured against if a prescribing decision is later challenged.

The Specials Manufacturing route

Most unlicensed CBPMs reach UK patients through the “specials” route. Under MHRA rules, an unlicensed medicinal product may be manufactured and supplied to meet the special clinical needs of an individual patient, where no suitable licensed equivalent is available. Manufacture requires a Manufacturer’s “Specials” Licence (MS) issued by the MHRA, and the manufacturing site must hold a valid GMP certificate. For cannabis-derived material, the Home Office Controlled Drug licence sits alongside the MHRA authorisations.

What this means at the prescriber’s desk:

1. A CBPM prescribed as a special must be for a named patient with a documented clinical need.
2. The product may not be advertised to the prescriber or the public; this constrains how clinicians may evaluate options.
3. The prescriber carries personal professional responsibility for the choice of unlicensed product, even where a pharmacy or supplier is involved in sourcing.

The mechanics: CD prescription forms, registers and audit

CBPMs are Schedule 2 controlled drugs. Practically, that means:

• Private prescriptions must be written on form FP10PCD in England (equivalent forms apply in the devolved nations). The form must be completed in the prescriber’s own handwriting only where required, but in all cases the dose, form, strength and total quantity in words and figures must be unambiguous.
• Prescriptions are valid for 28 days from the appropriate date and the quantity prescribed should ordinarily not exceed 30 days’ supply.
• A CD register must be maintained at the supplying pharmacy with running balances reconcilable at any time.
• Storage at the dispensing point must meet BS 7558 (or equivalent) standards for CD safes.
• The MHRA, GPhC and local Controlled Drug Accountable Officer all have inspection and audit roles.

Clinicians initiating CBPMs are also expected to contribute to the NHS England patient registry for CBPMs, established in April 2021. Reporting expectations sharpened in 2022 and the registry remains the most important national data-collection mechanism for this prescribing cohort.

NHS versus private pathways

NHS prescribing of unlicensed CBPMs remains highly constrained. Specialised commissioning routes exist for the small number of licensed products (Epidyolex for Lennox-Gastaut, Dravet and tuberous sclerosis complex; Sativex for MS spasticity in line with NICE), but routine NHS funding for unlicensed CBPMs is rare. The bulk of CBPM prescribing in the UK is therefore through private specialist clinics, with the patient bearing the cost of consultation and supply.

NIHR-backed clinical trials in refractory epilepsy, announced in October 2024, are an important parallel route. Specialists with eligible patients should be aware of trial inclusion criteria as a first-line consideration before initiating off-registry unlicensed prescribing.

Common reasons prescriptions are challenged

From regulatory case work and indemnifier feedback, the recurring problems are:

• Inadequate documentation of prior licensed-medicine trials and their outcomes.
• Absence of an MDT discussion record for complex cases, particularly paediatrics.
• Initiation by a clinician whose specialty does not match the clinical indication.
• Insufficient consent documentation around the unlicensed status of the product.
• Poor handover where a private specialist asks an NHS GP to take over prescribing without a clear shared-care framework.

The role of MDTs

Multidisciplinary input is not a statutory requirement for every CBPM prescription, but it is rapidly becoming the professional norm — especially for paediatric epilepsy, complex pain and any case where a regulator might later ask “what other view did you seek?”. Many private clinics now operate internal MDT panels with a neurologist, pain specialist, pharmacist and clinical nurse specialist. The documented MDT record is, in practice, the most useful single piece of audit defence a prescriber can hold.

Practical checklist before initiating

1. Confirm your GMC Specialist Register entry covers the relevant specialty.
2. Document failure or intolerance of licensed alternatives.
3. Hold an MDT or peer discussion and record the outcome.
4. Obtain written informed consent specifying the unlicensed status.
5. Use the correct CD prescription form and supply route.
6. Confirm the supplying pharmacy holds appropriate authorisations and audit trail.
7. Register the patient with the NHS England CBPM registry where applicable.
8. Plan a review and exit strategy at initiation, not only at review.

About MUZO Health

MUZO Health was created to raise the standard of cannabis-based medicines in the UK, with a focus on quality, consistency and clinical integrity. Our mission is to support clinicians, empower patients and help move cannabis medicine forward responsibly, transparently and without compromise. Learn more about MUZO Health.