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 harm potential (Class A: heroin, cocaine, MDMA; Class B: cannabis, codeine, ketamine; Class C: benzodiazepines, anabolic steroids)
- Misuse of Drugs Regulations 2001: 5 schedules governing prescribing, supply, and record-keeping
- Schedule 2 (morphine, diamorphine, fentanyl, oxycodone, methylphenidate): full CD prescription requirements, safe custody, register
- CD prescription legal requirements: patient name/address/DOB, drug name/form/strength/dose, total quantity in WORDS and figures, prescriber signature and date
- Schedule 2 CDs must be stored in a locked CD cupboard and documented in the CD register
Overview
Controlled drugs (CDs) are substances subject to legal controls due to their potential for misuse, harm, or dependence. The Misuse of Drugs Act 1971 classifies drugs into three classes (A, B, C) based on harm, determining criminal penalties for possession and supply. The Misuse of Drugs Regulations 2001 divides CDs into five schedules that govern legitimate medical use: prescribing requirements, record-keeping, storage, and disposal. Healthcare professionals must comply with both the legal framework and local Trust CD policies. The Shipman Inquiry (2004) led to significant strengthening of CD governance, including the role of Accountable Officers and more rigorous monitoring of CD prescribing and use.
Epidemiology
Opioid prescribing in England increased significantly over the past two decades, with growing concerns about dependence and diversion. There are approximately 300,000 high-risk opioid users in England. Drug-related deaths have been rising, with opioids being the leading contributor. Appropriate CD governance in healthcare settings is essential to prevent diversion, errors, and patient harm.
Clinical Features
Symptoms
This topic covers legislation and prescribing requirements rather than a clinical condition
Signs
Investigations
First-line
CD register checkRunning balance of all Schedule 2 CDs must be maintained and regularly audited
Prescription validity checkCD prescriptions must meet all legal requirements — pharmacists must verify before dispensing
1
Schedules (key ones for exams)
- Schedule 1: NO medical use, research only — LSD, raw cannabis, MDMA, psilocybin
- Schedule 2: HIGH abuse potential, medical use — morphine, diamorphine, fentanyl, oxycodone, methadone, methylphenidate, amphetamines. Full CD prescription and register requirements
- Schedule 3: Lesser abuse potential — buprenorphine, midazolam, temazepam, barbiturates, tramadol. CD prescription requirements but NO register requirement (except temazepam)
- Schedule 4: Low abuse potential — Part I: benzodiazepines (diazepam, lorazepam), zopiclone, zolpidem. Part II: anabolic steroids. Minimal CD requirements
- Schedule 5: Preparations containing low doses of CDs — codeine linctus, co-codamol, kaolin + morphine. No special prescribing requirements
2
CD prescription requirements (Schedule 2 and 3)
- Must be written in INK, signed by the prescriber
- Patient full name, address, and date of birth
- Drug name, form, strength, dose, and total quantity in WORDS AND FIGURES
- Date of prescription
- Valid for 28 days from the date of signing
- Electronic CD prescriptions are now permitted from approved systems
3
Storage and record-keeping
- Schedule 2 CDs: stored in a locked, immovable CD cupboard with restricted access
- CD register: records receipt, administration, and disposal of Schedule 2 CDs
- Two-person witnessed administration and destruction
- Accountable Officer (usually a senior pharmacist or medical director) oversees CD governance
Complications
- Diversion: CDs diverted from healthcare settings for misuse
- Prescribing errors: Incorrect CD prescriptions are legally invalid and cannot be dispensed
- Criminal liability: Illegal possession, supply, or prescribing of CDs carries severe penalties
- Patient harm: Opioid dependence from inappropriate prescribing
UKMLA Exam Tips
- 1Schedule 2: morphine, diamorphine, fentanyl, oxycodone, methadone, methylphenidate — full CD requirements
- 2Schedule 3: tramadol, buprenorphine, midazolam, temazepam — CD prescription but usually no register
- 3CD prescription must include: total quantity in WORDS AND FIGURES — classic exam question
- 4CD prescriptions are valid for 28 days
- 5Class A (highest penalties): heroin, cocaine, MDMA, LSD, methadone, morphine, fentanyl
- 6Class B: cannabis, codeine, ketamine, amphetamines
- 7Class C: benzodiazepines, GHB, anabolic steroids
- 8FY1 doctors CAN prescribe controlled drugs (all schedules)
practicetest your knowledge on controlled drugsApply what you've learnt with UKMLA-style questions from the iatroX Q-Bank — clinical pharmacology and beyond.
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