About This Page
This is a clinician-written, evidence-based summary aligned to the 2026 MLA Content Map. It is intended for medical students and junior doctors preparing for the UKMLA. Always cross-reference with NICE guidance, local protocols, and clinical judgement.
The Bottom Line
- Misuse of Drugs Act 1971: classifies drugs by harmfulness (Class A: heroin, cocaine, MDMA. Class B: cannabis, amphetamines. Class C: benzodiazepines, GHB)
- Misuse of Drugs Regulations 2001: 5 schedules controlling prescribing, dispensing, and record-keeping. Schedule 2 (morphine, diamorphine, fentanyl): full CD prescription requirements
- CD prescription requirements: handwritten/indelible, patient name/address/DOB, drug name/form/strength/dose/total quantity in words and figures, prescriber signature, date
- Off-label prescribing: legal and ethical if it is the best available option, patient is informed, and clinical responsibility is accepted by the prescriber
- GMC Good Practice in Prescribing (2024): prescribe within competence, based on evidence, with patient consent and clear documentation
Overview
Prescribing carries significant legal and ethical responsibilities. The legal framework includes the Medicines Act 1968 (classification of medicines), the Misuse of Drugs Act 1971 (control of harmful drugs), and the Misuse of Drugs Regulations 2001 (practical prescribing and supply requirements). Healthcare professionals must prescribe within their competence, based on best available evidence, with adequate assessment and monitoring. Off-label and unlicensed prescribing is common (particularly in paediatrics and palliative care) and is legally permitted provided the prescriber takes full clinical responsibility. The GMC's guidance "Good Practice in Prescribing and Managing Medicines and Devices" (updated 2024) sets the professional standard.
Epidemiology
Over 1.1 billion prescription items are dispensed in England each year. Prescribing errors occur in approximately 5-10% of hospital prescriptions, though most are minor. Controlled drug misuse is a significant public health issue — opioid-related deaths have been rising in the UK, with over 2,000 opioid-related deaths per year. The Shipman case (Dr Harold Shipman used diamorphine to kill patients) led to major reforms in controlled drug governance, including the introduction of Controlled Drug Accountable Officers in 2006.
Legal Framework
Symptoms
Schedule 1 (e.g. LSD, MDMA, raw cannabis): no medical use — cannot be prescribed. Possession requires Home Office licence
Schedule 2 (e.g. morphine, diamorphine, fentanyl, oxycodone, methadone, methylphenidate): full CD requirements — safe custody, registers, specific prescription format
Schedule 3 (e.g. midazolam, buprenorphine, tramadol, temazepam): CD prescription format required (except temazepam), but no register requirement for most
Schedule 4 (e.g. diazepam, zolpidem, anabolic steroids): subject to record-keeping but minimal restrictions on prescribing
Schedule 5 (e.g. codeine <13.5 mg/dose, pholcodine): minimal restrictions — can be sold OTC
Signs
Medicines classification: POM (prescription only), P (pharmacy only), GSL (general sale list)
Prescribers: doctors, dentists, independent prescribers (nurses, pharmacists), supplementary prescribers (PGD/protocol)
Key Principles
First-line
CD prescription requirementsSchedule 2 and 3: must include patient name, address, DOB, drug name, form, strength, dose instructions, total quantity in words AND figures, prescriber signature and date. Valid for 28 days from date of signing
CD registersSchedule 2 drugs: must be recorded in a bound, page-numbered register. Entries must not be cancelled or altered. Separate register per drug. Kept for 2 years
Second-line
Off-label prescribingLegal and ethical if: best available option for the patient, patient is informed it is off-label, prescriber accepts full clinical responsibility, and it is based on clinical evidence
Unlicensed medicinesMore restrictive — generally should only be used when no suitable licensed alternative exists. GMC requires: clear clinical need, evidence base, informed consent
Specialist
Yellow Card reportingMHRA Yellow Card scheme: report suspected adverse drug reactions — mandatory for new drugs (black triangle ▼) and all serious reactions
Controlled Drug Accountable OfficerPost-Shipman safeguard: each NHS trust/CCG must have an Accountable Officer responsible for safe management of controlled drugs
Management
GMC Good Practice in Prescribing (2024), Misuse of Drugs Act 1971, Misuse of Drugs Regulations 20011
Safe prescribing principles
- Only prescribe within your competence and scope of practice
- Adequate assessment of the patient before prescribing
- Check allergies, interactions, renal/hepatic function, pregnancy/breastfeeding
- Clear documentation: drug, dose, route, frequency, duration, indication
- Monitor for efficacy and adverse effects
- Review and stop medications when no longer needed (deprescribing)
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Prescribing for self, family, and colleagues
- GMC guidance: avoid prescribing for yourself or anyone with whom you have a close personal relationship
- Exception: minor illness or emergency only, no one else available, and the condition is within your competence
- Never prescribe controlled drugs for yourself
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Conflicts of interest
- Declare any financial or non-financial interests that could influence prescribing decisions
- Do not accept gifts, hospitality, or financial inducements from pharmaceutical companies that could influence prescribing
- ABPI Code of Practice governs pharmaceutical industry interactions with prescribers
Complications
- Prescribing errors: Wrong drug, wrong dose, wrong patient — leading cause of preventable harm in hospitals
- Controlled drug diversion: Theft or misuse by healthcare staff or patients
- Addiction: Iatrogenic opioid/benzodiazepine dependence from inappropriate prescribing
- Professional consequences: GMC investigation, loss of licence to prescribe, criminal prosecution for CD offences
UKMLA Exam Tips
- 1Schedule 2 = full requirements (safe custody, register, specific prescription format). Know the drugs: morphine, diamorphine, fentanyl, oxycodone, methadone, methylphenidate
- 2CD prescriptions are valid for 28 days from signing. Total quantity must be in words AND figures
- 3Off-label ≠ illegal. It is legal and ethical if clinically justified, patient informed, and prescriber accepts responsibility
- 4Class A drugs carry the highest penalties for illegal possession/supply (Class A > B > C). Do not confuse with Schedules (which govern medical prescribing)
- 5Yellow Card reporting: all reactions for new drugs (▼), all serious/unexpected reactions for established drugs
- 6Never prescribe CDs for yourself. Avoid prescribing for family/close contacts except in emergencies
practicetest your knowledge on prescribing ethics and controlled drugsApply what you've learnt with UKMLA-style questions from the iatroX Q-Bank — ethics & law and beyond.
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